CN205580953U - Concrete cracking overall process emulation testing machine - Google Patents

Concrete cracking overall process emulation testing machine Download PDF

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Publication number
CN205580953U
CN205580953U CN201620131497.5U CN201620131497U CN205580953U CN 205580953 U CN205580953 U CN 205580953U CN 201620131497 U CN201620131497 U CN 201620131497U CN 205580953 U CN205580953 U CN 205580953U
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China
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test specimen
fixed
deformation
chuck
concrete
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刘毅
张国新
王振红
杨德明
李建彬
张各亮
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China Institute of Water Resources and Hydropower Research
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China Institute of Water Resources and Hydropower Research
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Abstract

The utility model provides a concrete cracking overall process emulation testing machine, including the base, be equipped with on the base: an environment case separates with the surrounding environment, a concrete sample holding device is established in this environment case, and including fixed chuck, active clamp, the fixed side form board in test piece middle part, the amalgamation constitutes a concrete sample accommodation space, and fixed chuck sets firmly in the environment case, the movably setting of active clamp, temperature sensor is established to environment case and concrete sample accommodation space, a true environmental simulation system, it includes at least that a temperature regulation apparatus establishes the true environment of setting for with simulation in the temperature in environment case and concrete sample holding device, a loading system for active clamp rigidity or remove at the axis direction sets up the deformation of displacement deformation sensor perception concrete sample on active clamp, if answer the load that force transducer perception test piece bore. Experimental angle can be followed to this device, tests in the development overall process under the changeable ambient condition factors such as the temperature of concrete and stress.

Description

Concrete cracking whole process simulation testing machine
Technical field
This utility model belongs to Hydraulic and Hydro-Power Engineering technical field, relates to a kind of concrete cracking overall process test method based on true environment and uses the testing machine of the method, more particularly, to the device of the cracking whole process simulation test of mass concrete.
Background technology
For a long time, " not splitting without dam " is always unsolved world-famous puzzle, and the appearance in crack affects the outward appearance of dam structure, performance and safety, eventually affects the people's lives and property.How to reduce and even prevent the generation in crack from just becoming the problem that engineering construction person must take into.Along with association area is theoretical and the progress of technical research, the research work in dam concrete crack achieves significantly progress, particularly Temperature Controlling of Mass Concrete anticracking work, has the most defined rationale and the method system of comparatively perfect.But in view of the complexity of Hydraulic and Hydro-Power Engineering, the particularly abominable of location environment, dam concrete crack problem the most thoroughly solves.
The factor causing concrete generation crack is a lot, structure, material and construction factor are all likely to become the inducement that crack occurs, but for dam, the dam particularly built in big temperature difference high altitude localities, around weather environment is increasingly becoming the emphasis factors that temperature controlled anticracking controls.Atmospheric environment not only surrounds whole concrete works in real time, and the changeable of atmospheric environment also produces important impact to engineering, the particularly factor such as the temperature of surrounding, humidity, rainfall, wind speed and solar radiation, drastically influence the generation of distress in concrete, the affecting laws that distress in concrete is produced by atmosphere environment impact factor how, its influence degree has again much, there is presently no final conclusion.Therefore, needed for development concrete cracking overall process testing machine based on true environment and method just become dam concrete engineering construction.
It addition, at present, for there is a lot of weak point on test specimen displacement or deformation measurement in prior art:
1. most measurement apparatus use indirect measure or foil gauge to measure test piece deformation, and its precision is difficult to satisfactory.
2. for many testing machines, will test in various simulated environment for test specimen, various environment bring the biggest impact for the certainty of measurement of displacement, deformation so that certainty of measurement is the highest.
3. in prior art, ftracture research aspect to concrete material, the most employing temperature stress testing equipments, it is impossible to accurately measure the deflection of early concrete cracking, analyze and evaluate the cracking trend of concrete, not up to the ideal effect of research.
The most existing test specimen displacement or deformation measuring device, the gauge length being limited to various displacement deformation sensor is many at below 200mm, for length test specimen more than 1 meter, it is difficult to deformation or displacement to test specimen are given and the most reasonably measure.
Further, testing machine of the prior art, it is rigid element that test specimen accommodates parts, and centering is poor.
Utility model content
The purpose of this utility model is to improve the limitation in the simulation of existing concrete temperature stress and crack research and deficiency, there is provided a kind of from test angle, the concrete cracking whole process simulation testing machine that the factor development overall processes under the conditions of changeable environment such as the temperature of concrete and stress are tested.
Technical solution of the present utility model is:
The concrete cracking whole process simulation testing machine that this utility model provides, including a base, is provided with on the base
One environmental cabinet, at least has four walls and upper cover, forms a space closed, separates with surrounding;
One concrete sample accommodating device, it is arranged in this environmental cabinet, it includes fixed bolster plate in the middle part of fixed chuck, active chuck, test specimen, three's split constitutes a concrete sample accommodation space that upper end is uncovered or upper and lower side is the most uncovered, described fixed chuck is fixedly installed in this environmental cabinet, described active chuck can be arranged movably along the axis of the length direction of described concrete sample accommodation space, and described side template is placed between fixed chuck and active chuck;
At described environmental cabinet or described environmental cabinet and concrete sample accommodation space, temperature sensor and humidity sensor are set;
One true environment analog systems, it at least includes a temperature-adjusting device, and it is heating and/or heat sink, and it is arranged on described environmental cabinet and concrete sample accommodating device and at least proposes fixed true environment in temperature upper mold to provide;
One loading system, including a reaction frame, an actuating device and one with the servomotor of reductor, described reaction frame is arranged on described base, this actuating device includes a ball-screw charger, the driven member connection constraints axle that leading screw is for linear motion is connected on this charger, this constraint axle is connected with described active chuck by the sidewall entrance environmental cabinet of described environmental cabinet and this active chuck position is fixed or moves at described axis direction, and the driving link leading screw in this charger is fixed on this reaction frame;Described servomotor is arranged on described reaction frame, connects described leading screw;This servomotor constitutes load and execution mechanism, and described reductor is worm reduction gear, and described constraint axle uses invar steel (invar) to manufacture;
Described active chuck or the parts that are connected with active chuck arrange the deformation of displacement/deformation-sensor perception concrete sample;
Described ballscrew charger arranges the load that strain gauge perception test specimen bears.
With described testing machine suitably, also including a computer, this computer is connected by data wire and a control system, and this control system includes: control the control unit of master trip machine true environment analog systems each actuator action;With the control unit of servomotor action described in control concrete sample loading system in master trip machine;
Described computer is also by the signal output part of the temperature sensor of monitoring of environmental parameter described in data wire;
The signal output part of the displacement/deformation-sensor of the displacement/deformation of described monitoring concrete sample;
The signal output part of the strain gauge of described monitoring test specimen stress is connected;
The control signal outfan of described control system is connected with the control end of each actuator.
Temperature control unit accepts the instruction of computer, controls the work of actuator i.e. heating/cooling device so that concrete sample accommodation space can also include that the temperature of environmental cabinet meets the parameter of setting.
Displacement/deformation control unit controls the described servomotor in actuator i.e. loading system together with Loading Control unit.
Data handling system in computer calculate concrete sample in the true environment of described simulation include restraint stress, free variable, elastic modelling quantity, deformation separate, creep at least one result exporting.
Including the rock deformation sensor being arranged in environmental cabinet and two built-in fittings being arranged in test specimen, built-in fitting arranges quartz measuring staff, this measuring staff one end is fixed with the built-in fitting near fixed chuck side, the other end is positioned close on the built-in fitting of active chuck side and can relatively slide axially along test specimen by this built-in fitting, described quartz measuring staff is corresponding with rock deformation sensor, to be measured the displacement of quartz measuring staff by rock deformation sensor (rock extensometer), directly measure the deflection of test specimen;And/or,
Including the extension bar installed on the grating sensor being arranged on outside described environmental cabinet and the built-in fitting arranged in test specimen, perforate on described environment tank wall, it is corresponding with the grating sensor being arranged on outside environmental cabinet that this extension bar stretches out described environmental cabinet, to measure the relative displacement of the extension bar on built-in fitting, measure test piece deformation amount.
The shape of cross section of described accommodation space is: two ends are the heads that width greater depth is shorter, and centre is the interlude that width smaller length is longer, and described head and interlude connect transition by cone section;In the range of in the middle part of described fixed chuck and active chuck and test specimen, splicing seams between fixed bolster plate is positioned at the interlude of this accommodation space.
Two described built-in fittings are preferably disposed in the test specimen relative to described head.
Extension bar on each built-in fitting is two, laterally stretches out from the two opposite side walls of environmental cabinet, corresponding with two grating sensors being arranged on outside environmental cabinet.With this, the deformation of test specimen can be detected more accurately, eliminate measurement error.
The built-in fitting arranged in test specimen for fixed displacement/deformation-sensor, it includes the inlet part being arranged in test specimen concrete, exposes the disk body on concrete sample surface and deck, described inlet part is a plate body, the plate face of this plate body is perpendicular to the described axis of described concrete sample accommodation space, the card of the disk body being connected with inlet part is vertical with the plate body plate face of described inlet part, arranges deck and the support bar of the quartzy measuring staff being connected described temperature sensor composition coupling clamping structure on this disk body.
Further, described test specimen houses fixing device can also include a cope match-plate pattern, and its described upper end closing described concrete sample accommodation space is uncovered.
Seam between described side template and described active chuck and/or fixed chuck leaves gap, this gap includes the gap between the termination of side template and described active chuck, to ensure test specimen side template and active chuck non-contravention when compression, also include the gap between the side of side template and fixed chuck and active chuck.
Described side template can be arranged in this environmental cabinet transverse shifting.
In use, concrete directly can be poured in described concrete sample accommodation space formation test specimen, it is also possible to be placed in described concrete sample accommodation space by the test specimen with this test specimen accommodation space form fit made.
It is arranged on the heating in the described climate control system in described environmental cabinet and/or chiller can be provided in the tank wall of described environmental cabinet or in the space closed, described tank wall has hollow chamber, and/or, described fixed chuck, active chuck and the side template at least one that test specimen houses in fixing device is set there is hollow chamber;
Each described hollow chamber arranges inlet and outlet and connects with the medium channel of described heating and/or heat sink, described actuator can be the delivery pump of the electrical heating coil arranged on the medium channel of this heating-cooling device or the media flow driving heating or cooling, for providing heat energy or cold energy the most as required.
In this utility model, climate control system main in simulation true environment system, can there be two parts, a part is to arrange on environment casing, and another part houses at test specimen and arranges in fixing device.Environmental cabinet is arranged, is more the temperature in simulation true environment, and houses at test specimen and arrange in fixing device, the temperature of such as concrete dam in true environment can be simulated at short notice.Testing machine of the prior art does not all have the most comprehensively climate control system.
In this utility model, can directly concrete be cast directly in the concrete sample accommodation space that test specimen houses fixing device, so, just can test concrete in the true environment of simulation from lean state to solidification again to dilatancy and the change of stress of hardening complete procedure, so, such as dam be can be carried out testing from pouring, be solidified to the stress of hardening process, strain under difficult environmental conditions, it is thus achieved that comprehensively data, for design, the information providing valuable of constructing of dam.Testing machine of the prior art does not all expect the test yet not accomplishing this complete procedure.Certainly, the test specimen in the testing machine that this utility model provides houses fixing device and can also test the concrete sample made.
Attachment structure between described constraint axle and described active chuck is for being articulated and connected.Thus so that connecting ball pivot seat can be the most freely rotatable, it is to avoid during loading, test specimen is produced torsional load, bias is had fine adjustment function.
Specifically, the termination of described constraint axle is bulb, and the ball pivot seat that described active chuck is arranged is two halves formula structures.
Concrete structure is: described ball pivot seat includes front ball seat and rear ball seat, described front ball seat is fixed in the both ends of the surface of described fixed chuck and active chuck, rear ball seat is fixed on front ball seat by pretension bolt, front ball seat and rear ball seat constitute the spherical space accommodating constraint shaft end bulb, and forward and backward ball seat coordinates and reserves certain interval at plane, can be by adjusting the pretightning force size of pretension bolt for when mounted, ensure that bulb is very close to each other with the connection sphere of ball seat, it is to avoid draw, press loading when switching, to produce idle running impact.
The computer control system that this utility model provides is substantially prior art, implement function such as wherein: when pushing against described active chuck owing to test specimen deforms in the true environment of simulation, strain gauge collects stress, signal output part and power set by data handling system and data output system are connected and start power set and drive active chuck to move until the stress of sensing is reduced to zero on strain gauge, and described power set stop.
Such structure is so that this testing machine realizes the tests such as free variable.
Also having is exactly after free variable, starts power set and drives active chuck to move and reduce deflection, institute's displacement sensors obtains displacement, described strain gauge obtain corresponding stress value.
Described true environment analog systems is in addition to described air conditioner, at least one adjusting means arranging in described environmental cabinet can also be included: humidity control apparatus, solar radiation adjusting means, rainfall adjusting means, wind-speed adjusting device, correspondingly, at least one in also including such as lower sensor: humidity sensor, solar radiation sensor, rainfall sensor and air velocity transducer, it is connected with described computer, the described actuator that described control system connects.
Specifically, can on the tank wall of described environmental cabinet apertured, connecting line, this pipeline connects supplies gas, send at least one in vapour, air-supply and water injector, correspondingly constitutes humidity control apparatus, rainfall adjusting means and wind-speed adjusting device;And/or, apertured on the tank wall of described environmental cabinet, hole arranges the light fixture composition solar radiation adjusting means that simulated solar irradiates.
Each actuator associates the true environment so that simulating setting with described control system.
Each described adjusting means can also is that establishes one's own system, such as temperature-adjusting device, and including heating controller, temperature controller, it connects heating element heater and temperature sensor and realizes heating function.As such, it is possible to the structure of simplified control system.
Further, described framework is the framework of the rectangle including two crossbeams and two column compositions, one fixed cross beam is fixed on the described base of described fixed chuck side, two described columns described fixed cross beam that is connected abreast is positioned at described environmental cabinet both sides, one fine motion crossbeam is arranged on the described base of described active chuck side, it is connected with described column, described power set are arranged on this fine motion crossbeam, it is consequently formed reaction frame, described straight-line motion mechanism is connected through this fine motion crossbeam with active chuck, the support section of described displacement/deformation-sensor and described strain gauge is fixed on described base directly or indirectly.
The framework that this utility model provides, two one, crossbeams are fixed on described base formation fixed cross beam, and another is provided on described base not having fixed structure to form fine motion crossbeam with this base, and loading system is arranged on fine motion crossbeam.
So, when loading system exerts a force to test specimen, framework can bear the biggest stress and there may be the least deformation, but this power and deformation will not pass to base.Therefore, the certainty of measurement of displacement transducer and force transducer is not affected by frame deformation, it is ensured that well certainty of measurement.
Described constraint axle can manufacture with invar steel 4J36.
The material of described column and sectional dimension be: ensures power that its rigidity is 5-20 times that bears the maximum strength stress of concrete and indeformable, or stiffness K is more than or equal to 2MN/mm;And/or, it is ensured that when its temperature stability is in the temperature range (such as-20-80 DEG C) of test, its temperature deformation is less than 10 microns.
The described framework that this utility model provides, uses upright post cross-beam type, Stability Analysis of Structures, and column the most therein has enough rigidity and temperature deformation stability, can the precision of guarantee test well.
Further, the described case lid of described environmental cabinet arranges form so that process of the test visualizes.
Servomotor selected by described power set, connects worm reduction gear drive mechanism.So make the big raising of control accuracy, feedback speed, efficiency.
A hoisting mechanism is also set up at described base, house at described test specimen and fixing device arranges a base plate for placing test specimen or pouring into a mould test specimen thereon, this base plate connects this hoisting mechanism, by running this hoisting mechanism, it is possible to by test specimen from concrete sample accommodation space into and out.
The testing machine that this utility model provides can also include an ancillary test machine, this ancillary test machine includes that a test specimen containing cavity is for placing the test specimen identical with the test specimen of test in described master trip machine, this test specimen containing cavity arranges described temperature-adjusting device, or at least one in described temperature-adjusting device and following adjusting means is set: humidity control apparatus, solar radiation adjusting means, rainfall adjusting means and wind-speed adjusting device;This test specimen containing cavity arranges temperature sensor, at least one in also setting up such as lower sensor: humidity sensor, solar radiation sensor, rainfall sensor and air velocity transducer, each described sensor is connected with described computer, and this control system connects described adjusting means and regulates described test specimen to house the cavity environment parameter identical with described master trip environmental cabinet;This test specimen containing cavity also sets up the deformation with perception test specimen of the displacement/deformation-sensor.
Displacement/the deformation-sensor arranged in ancillary test machine can be identical with master trip machine.
Described control system also includes the control unit controlling the various described actuator action of true environment analog systems in described ancillary test machine.
Test specimen containing cavity put into by test specimen as master trip machine so that test specimen can Free Transform.Test specimen in same environment in ancillary test machine, for contrasting with the test specimen in master trip machine.Ancillary test machine is under the conditions of test specimen and machine bed plate coefficient of friction are sufficiently small, measurement and the master trip machine Free Transform of auxiliary test specimen under the conditions of synthermal.Synthermal condition parallel test machine, makes test data possess integrity.
The testing machine that this utility model provides, is mainly used in distress in concrete mechanism and temperature stress test.Under the conditions of can carrying out multiple temperature control measures, concrete is from being poured into the test of evolution of himself temperature stress hardening overall process, and this process can include the process that adiabatic temperature rise, thermal coefficient of expansion, elastic modelling quantity and the parameter such as creep develop in time;With analog simulation true weather environment, the temperature stress under the influence of natural cause and Cracking Mechanism can be emulated.This testing machine can be arranged as required to different temperature and constraint degree condition, including thermal insulation, constant temperature, the process etc. of setting temperature rise temperature drop.Tested by concrete cracking whole process simulation, evaluate the cracking resistance of concrete.
The concrete cracking whole process simulation testing machine that this utility model provides, it is that test piece deformation amount concrete cracking whole process simulation testing machine directly measured by band, including master trip machine, or also include ancillary test machine, it addition, also include that Measurement and Control System, electric dragging system, heating refrigeration system, computer control and processing system.
Described master trip machine includes reaction frame, speed reducer for servo motor ball-screw charger, test specimen temperature template, mould emptier, constraint axle, thermal environment case.0-100% retrains, and by servomotor push pull maneuver, carries out retraining control, the temperature during measurement concrete is the most full-fledged and stress, and temperature during cracking and stress to the expansion or shrinkage of concrete.And auxiliary testing machine is with master trip machine without constraint axle, principle and other structures.
Described Measurement and Control System includes deformation under load Measurement and Control System and Temperature Measure Control System, comprises industrial computer, digital multichannel closed loop controller, data collecting card, load sensor, displacement transducer, deformation-sensor, temperature sensor and humidity sensor etc..Real time data is fed back to controller or data collecting card by sensor, and computer controls and display result.Restraining forces, deformation, temperature, humidity etc. suffered by test specimen are mainly measured and control by system.
Described electric dragging system is formed execution unit, the instruction that execution controller and control system send by the chopper of all size, relay, DC source, servo-driver and push-botton operation part etc., carries out process control.
Described heating refrigeration system includes heater, refrigeration compressor set, water pump, couveuse and pipe valve.
Described computer controls and processing system includes industrial computer, laser printer, control and data processing software, the control instruction that Measurement and Control System is sent, accept the pressure of Measurement and Control System collection, displacement, deformation numerical value, show according to instruction or export the control instruction that Measurement and Control System is sent with curve by various chart.
Use above-mentioned testing machine, concrete cracking overall process test method based on true environment, comprise the following steps:
(1), concrete is cast in described concrete sample accommodation space, or concrete sample is arranged in this concrete sample accommodation space in fixing device;The two ends of described test specimen are connected with described fixed chuck and active chuck respectively;
(2) a true environment analog systems is built, the at least temperature parameter in described environmental cabinet and/or concrete sample accommodating device is made to reach to set true environment requirement to be simulated by described actuator, environment in this environmental cabinet can be a constant environment, or the environment in the change of set point intrinsic parameter;
(3) under the true environment set, at least one following test procedure is then carried out:
The most freely retrain:
Concrete sample one end is fixed by testing machine, other end retractable, under true environment analog systems provides the true environment set, this test specimen is carried out free variable test, in the time zone (t) set, set period collection deflection ε (t)
When there is expansion or shrinkage in test specimen, the strain gauge arranged i.e. demonstrates stress value, i.e. start power set so that straight-line motion mechanism until strain gauge display stress value is zero, obtains the numerical value of free variable now in the identical direction motion of deformation direction from displacement/deformation-sensor.
The concrete operations freely retrained are: the two ends of concrete sample are clamped by testing machine, one end is fixed, one end can control mobile, under true environment simulated conditions, described test specimen can be controlled end and be not added with load, set time interval (t), the data detected according to displacement/deformation-sensor and strain gauge, make power set action by control system, thus, the free displacement making described test specimen is μ (t), is free variable ε (t) of t concrete.
The free variable purpose measuring concrete is to separate for the various deformation of concrete.
B. restraint stress:
The two ends of concrete sample are clamped by testing machine, one end is fixed, one end can control mobile, freely stretch in the one end being connected with active chuck the most first allowing test specimen, after test specimen has an elongation or amount of contraction in described true environment, set time interval (t), the data detected according to displacement/deformation-sensor and strain gauge, power set action is made by control system, thus, the displacement making test specimen movable terminal reduces, the concrete stress in the case of the different degree of restraint of test, and this test specimen is carried out restraint stress test.
Concrete operations are: the two ends of concrete sample are clamped by testing machine, and one end is fixed, and one end can control mobile.Under true environment simulated conditions, the free displacement of described concrete sample movable terminal is μ (t), according to actual needs, by computer control system, displacement/Deformation control system and loading system, displacement to test specimen movable terminal reduces, and the most described strain gauge records concrete temperature stress σ (t) in the case of each moment difference degree of restraint is constraint factor f (t).
The displacement that movable terminal reduces is:
f(t)×μ(t) (6)
In formula, t is the time, and f (t) is concrete constraint factor during t, and μ (t) is the free displacement of concrete sample movable terminal.
C. elastic modelling quantity:
Concrete cracking overall process testing machine based on true environment measures the elastic modelling quantity of concrete, and set interval in the computer of computer △ t, i.e. every the elastic modelling quantity of a △ concrete of t measure of time.
Specifically, set interval △ t in a computer, every △ t time interval, the data detected according to displacement/deformation-sensor and strain gauge, power set action is made by control system, thus, test specimen movable terminal is made to do a change in displacement, i.e. for the change in displacement value (such as 2 microns) set, when piece lengths elongation or shortening length reach to set change in displacement value (such as 2 microns), test specimen movable terminal is done a change in displacement, this is set change in displacement value push back or pull back, the STRESS VARIATION that this change in displacement causes is measured according to strain gauge, this test specimen is carried out elasticity modulus test.
Concrete operations are: every the △ t time, the data detected according to displacement/deformation-sensor and strain gauge, power set action is made by control system, thus, test specimen movable terminal is made to do change in displacement Δ μ (t), it refers to the difference of the length in a moment and this moment on test specimen, draw deformation Δ ε (t), it refers to that on test specimen, the difference of the length in a moment and this moment is divided by test specimen total length, the STRESS VARIATION amount measured according to strain gauge is Δ σ (t), then the modulus of elasticity of concrete of t is:
E ( t ) = Δ σ ( t ) Δ ϵ ( t ) - - - ( 7 )
According to the time interval of design, computer control system can automatically be measured modulus of elasticity of concrete the most in the same time, i.e. can get the concrete elastic modelling quantity in whole evolution.
D. the separation deformed
The variations in temperature recorded according to thermal expansion coefficient of concrete and temperature sensor, draws the temperature deformation of concrete, in conjunction with the Free Transform recorded, the test to the separation that this test specimen deforms.
The separation of deformation refers to separate recording total deformation.Because recording total deformation is that various deformation mixes, there is the deformation (such as expanding with heat and contract with cold) that temperature causes, have the deformation that drying shrinkage causes, have autogenous volumetric deformation, have deformation that stress causes etc..Here separation, that part of the deformation such as only temperature caused is separated inside deformation from recording, to understand concrete deformation only under temperature action etc..
Concrete operations are: first do free constraint: concrete sample one end is fixed by testing machine, other end retractable, the true environment set is provided by true environment analog systems, this test specimen is carried out free variable test, in the time zone (t) set, set period collection deflection ε (t).
After 1 day age of concrete, its thermal coefficient of expansion would not change substantially again, it is considered that being a constant, this parameter can also be recorded by special thermal coefficient of expansion tester, here it is considered that it is constant α.Change in temperature Δ T (t) recorded according to thermal expansion coefficient of concrete α and temperature control system, it can be deduced that the temperature deformation of concrete under true environment simulated conditions:
ΔεT(t)=α Δ T (t) (8)
In conjunction with Free Transform ε (t) recorded, separate, can show that other deform Δ εaT (), mainly includes autogenous volumetric deformation and dry-shrinkage deformed:
Δεa(t)=ε (t)-Δ εT(t) (9)
E. concrete creep
The Free Transform that the modulus of elasticity of concrete recorded according to abovementioned steps C and abovementioned steps A record, can calculate not by concrete stress during Creep Effect;The data detected according to displacement/deformation-sensor and strain gauge, make power set action by control system, thus, the deformation making test specimen is zero, at this moment records another stress, according to the two STRESS VARIATION, this test specimen carries out the test of concrete creep.
Concrete operations are: according to modulus of elasticity of concrete E (t) drawn and Free Transform ε (t), can calculate under true environment simulated conditions not by concrete stress σ (t) during Creep Effect:
σ (t)=ε (t) E (t) (10)
The data detected according to displacement/deformation-sensor and strain gauge, make power set action by control system, thus, concrete deformation is controlled so that it is be deformed into zero, at this moment recording stress is σ0(t), then the stress caused of creeping under true environment simulated conditions is reduced to:
σc(t)=σ (t)-σ0(t) (11)
Pass through σcT the size of () can draw the influence degree of concrete creep, wherein t is the time.
F. concrete cracking overall process
Allow concrete sample bear tension in the variations in temperature set or in the simulation true environment set, apply pulling force until cracking, it is thus achieved that the temperature variations of concrete cracking or the tensile strength of concrete sample or limit stretch value in the true environment set.
The concrete operations of concrete cracking overall process may is that concrete temperature changes to design temperature from initial temperature, test specimen two ends are fixed, one end applies pulling force, when tension data reduce suddenly, displacement increases suddenly, corresponding time m-stress, time m-deformation/displacement curve on sudden change occurs time, concrete cracking, obtain the relevant parameter of at this moment concrete, including temperature, tensile strength, limit stretch value.
G. this test specimen is carried out concrete cracking overall process evaluation
Integrating step A, the test data i.e. experimental condition of B, C, D, E, F and result, carry out assessment of performance to concrete sample in the simulation true environment that test sets.
Further, test data and result in conjunction with above at least one A, B, C, D, E, F, i.e. combine relevant environmental parameter such as temperature, stress, displacement and the deformation of concrete, this test specimen carried out intact from concrete sample or start until cracking overall process makes evaluation from pouring.
In this step, can arrange multiple environmental factors variation model for weather environment change this feature complicated in engineering reality, described environmental factors parameter includes ambient temperature, comprises additionally at least one in humidity, rainfall, wind speed and solar radiation.
Relevant parameter temperature, stress, displacement and the deformation of concrete for engineering design as the cracking index under the conditions of real-world temperature, can be constructed and build the test reference providing important.
From the foregoing, the Free Transform of concrete under real environmental conditions can be tested by described testing machine and method;The temperature stress of concrete difference restrained condition under real environmental conditions can be tested;The elastic modelling quantity evolution of concrete under real environmental conditions can be tested;The various deformation of concrete under real environmental conditions can be carried out separation test;Concrete under real environmental conditions can be crept and test;Can be analyzed evaluating to the cracking overall process of concrete according to testing concrete temperature, stress, the isoparametric evolution of strain and the dehiscence process drawn under real environmental conditions, the Crack Control Design for concrete provides reference.
The simulation of described true environment, refers to, according to relevant informations such as Practical Project on-site hydrometeorology condition, input environment temperature, humidity, rainfall, wind speed and solar radiations, simulate real engineering weather environment.In this step, multiple environmental factors variation model can be set for weather environment change this feature complicated in engineering reality.
The method that this utility model provides, it is also possible to start until each stage of such overall process that ftractures or various aspects are tested and evaluated from concrete cast test specimen.
In the above-mentioned methods, for the simulation of true environment, can adopt with the following method:
1. ambient temperature
Depending on local situation, i.e. simulating the locality of true environment, above monthly mean temperature data fits to a cosine curve, following formula (1) is the computing formula after matching:
Consider climate simulation, use following formula to calculate:
T a = T a m + A a c o s [ n 6 ( τ - τ 0 ) ] - - - ( 1 )
In formula, TaFor temperature, TamFor average temperature of the whole year, AaFor temperature year luffing, τ is time (moon), τ0Time (moon) for maximum temperature.
Consider temperature diurnal variation, use following formula to calculate:
T a d = T a + A c o s [ π 12 ( t - 14 ) ] - - - ( 2 )
In formula,For daily temperature, TaFor monthly mean temperature, A is temperature diurnal variation amplitude, t be moment in 1 day (time) according to the Various Seasonal of different regions depending on.
2. solar radiant heat
Concrete structure is often exposed under solar radiation, and concrete temperature is had a major impact by it.The heat that in unit interval, solar radiation comes in unit are is S, wherein sets the part absorbed by concrete and is reflected as R, remainder, then:
R=αs·S (3)
In formula, αsFor absorptance, also referred to as coefficient of blackness, concrete surface typically takes 0.65.
S=S0(1-kn) (4)
In formula, S0For fine day solar radiant heat, n is cloud amount, and k is coefficient, and these three numerical value can be given by local weather station.
The impact at sunshine is equivalent to the temperature of surrounding air and increases Δ Ta,
ΔTa=R/ β (5)
In formula, β is concrete surface exothermic coefficient, can calculate according to surface roughness and wind speed.
3. rainfall
The rainfall of inquiry engineering location meteorological department, carrys out simulated rainfall by rainfall equipment and rainfall controller.
4. wind speed
The wind speed of the inquiry on-site meteorological department of engineering, threshold wind velocity analog, and concrete surface coefficient of heat transfer can be drawn according to wind speed.
Under the conditions of the testing machine that this utility model provides can carry out multiple temperature control measures, concrete is from being poured into the evolution of himself temperature stress hardening overall process, the process developed in time including adiabatic temperature rise, thermal coefficient of expansion, elastic modelling quantity and the parameter such as creep, with analog simulation true weather environment, the temperature stress under the influence of natural cause and Cracking Mechanism can be emulated.This device can be arranged as required to different temperature and constraint degree condition, including thermal insulation, constant temperature, setting temperature rise temperature drop process etc..Tested by concrete cracking whole process simulation, evaluate the cracking resistance of concrete.
This testing machine is the testing equipment of numerical simulation and visual simulating laboratory, is mainly used in distress in concrete mechanism and temperature stress test.Under the conditions of multiple temperature control measures can being carried out, concrete is from being poured into the evolution of himself temperature stress hardening overall process, the process developed in time including adiabatic temperature rise, thermal coefficient of expansion, elastic modelling quantity and the parameter such as creep, with analog simulation true weather environment, the temperature stress under the influence of natural cause and Cracking Mechanism can be emulated.This instrument can be arranged as required to different temperature and constraint degree condition, including thermal insulation, constant temperature, setting temperature rise temperature drop process etc..Tested by concrete cracking whole process simulation, evaluate the cracking resistance of concrete.
This test function is that test specimen provides the scleronomic constraint condition of at least 20 tons, 100% constraint, and can carry out 0~100% stepless adjustable;Realize temperature rise, the accurate simulation of temperature drop process, provide accurate boundary condition for concrete sample.By motor push pull maneuver, carry out retraining control to the expansion or shrinkage of concrete, measure the temperature in the development of concrete maturation and dehiscence process and stress.
Ancillary test machine is without constraint, and under the conditions of test specimen and machine bed plate coefficient of friction are sufficiently small, measurement and master trip machine be the Free Transform of auxiliary test specimen, synthermal condition parallel test machine under the conditions of synthermal, makes test data possess integrity.
These apparatus and method have the advantage that
1) this testing machine uses environmental cabinet and concrete sample accommodation space dual structure, can pour from test specimen and proceed by test, in addition various true environment can be simulated, can fully understand that concrete is poured into the situation of hardening complete procedure, provide comprehensive test data for industry-by-industry xoncrete structure.
2) have employed the reaction frame structure of high rigidity, be suitable to the permanent creep test of concrete.
3) have employed floating frame structure, i.e. two end floor beams, one is fixed on base, and one is only placed on base, and certainty of measurement is higher, and systematic error is less.
4) adding test specimen automatic lifting device, after making specimen molding and test, test specimen processing procedure saves muscle power, it is simple to operation;
5) add test specimen and adjust the function of constraint in process of the test, adjust this micro-adjusting mechanism in process of the test and test specimen constraint can be made to be gradually reduced to zero;
6) real-time tracking record data, sampling time interval can freely be arranged;
7) in described main frame, charger is to use servomotor Hardened gear face worm reduction gear ball-screw type of drive, servomotor and reductor with the use of, make loading system rotary inertia little, response time is short, stress loading lag time≤1S.Because turbine and worm decelerator has auto-lock function, with servomotor with the use of load long-time stable can be made to work, in time surveying this charger and be loaded into maximum load, stable load horizontal quasi exactness can maintain ± 0.05% within.Move because of reaction frame floating end during loading, and fixing end is motionless with test specimen fixed reference end, so measurement error will not be introduced.Use servomotor ball-screw method for designing so that it is total noise of centrifuge is less than 65dB;
In view of the demand of long term test, using full servomotor Hardened gear face worm reduction gear type of drive, the accuracy controlled than motor loading stress is greatly improved.In experimentation, concrete deformation is the least, and servomotor and reductor match uses, and servomotor speed is stepless adjustable, and loading step-length can arbitrarily select, therefore Bit andits control accuracy is higher than motor;Kind of drive ball-screw, higher than common leading screw precision, transmission efficiency the most much higher (95%), transmission uses rolling friction, and service life is long.
Reaction frame uses 45 steel makings, it is designed to one end and fixes the attachment structure of one end floating (fixing during transport), when reaction frame stress, its power and deformation are not transferred to base, and then with counter-force frame influence each other the deformation measurement to test specimen measure produce interference, measurement error will not be introduced.
Heat within environmental cabinet isolation transmits to reaction frame and base, and the heat simultaneously also completely cutting off outside internally transmits, it is ensured that temperature controlled easily-controllable property, avoids the rising-heat contracting-cold impact on measurement result of plant bottom case simultaneously.
Constraint axle front end is ball head structure, and connecting ball pivot seat can be the most freely rotatable, it is to avoid during loading, test specimen is produced torsional load, bias is had fine adjustment function.Ball pivot seat is two halves formula structures with the connection of bulb, can be by adjusting screw bolt pretightening force during installation, it is ensured that bulb is very close to each other with the connection of ball seat, it is to avoid draws, press loading to produce idle running impact when switching.
8) as a kind of optimization of above technical scheme, retraining axle in described main frame uses invar steel 4J36 to manufacture, the elastic modelling quantity of invar steel is big, linear expansion coefficient is the least, mainly for the manufacture of the element varying with temperature size approximately constant in precision instrumentation, the average linear coefficient of expansion in the range of 20~100 DEG C only has 1.4x10^-6/ DEG C, and it is basically unchanged when-80~100 DEG C, the error of experimental result can be calculated or measure, thus calculating or measurement error can be removed in final result, make result unaffected.
9) as a kind of optimization of above technical scheme, described deformation measurement uses grating sensor (resolution 0.1 μm) to be arranged on outside test specimen environmental cabinet, couple with test specimen built-in fitting, not affected by internal temperature and humidity, test piece deformation is accurately and reliably to measure to use strain-type rock deformation sensor (rock extensometer) mode.In process of the test, test piece deformation is by being embedded in the built-in fitting within test specimen, quartz measuring staff is driven to move, measuring staff one end is fixed with built-in fitting, the other end can slide axially along test specimen by built-in fitting relatively, measured the displacement of quartz measuring staff by rock deformation sensor (rock extensometer), directly measure the deflection of test specimen.Optimizing further, can install extension bar simultaneously on built-in fitting, employing is arranged on the grating sensor outside environmental cabinet and measures the relative displacement of the extension bar on built-in fitting, measures test piece deformation amount.Deformation-sensor precision is up to precision 0.1%FS (0.1 μ ε), uses temperature range-70 DEG C~180 DEG C.Because extensometer is output as analog quantity, range be the deformation-sensor (extensometer) of 2.5mm with 24 A/D (effective code 180,000) of total digital controller with the use of, minimum resolution is 0.014 μm, and control accuracy can 0.125 μm.Displacement measuring staff all uses quartz material with deformation measuring staff, and the average linear coefficient of expansion of quartz is only α 1 (-20~200 DEG C)≤0.55 × 10^-6/ DEG C, and on measuring, impact is the least, it is also possible to deduct in process of the test by demarcating mode.It is of course also possible to be used alone grating sensor to obtain displacement/deformation data.
10) as a kind of optimization of above technical scheme, described test specimen temperature template material is 304 Stainless Molding Boards, it is respectively lower bolster, two side templates and cope match-plate pattern, template thermometer hole 1 is all had in each template, cope match-plate pattern is separately disposed with three test specimen thermometric vias, for temperature sensor is inserted to inside test specimen, it is distributed at piece lengths 1/4,1/2 and 3/4, template and test specimen totally 7 each point for measuring temperature.Cope match-plate pattern placing flat, above test specimen, can freely remove and install, and circulation fluid junction uses hose connection, need not dismantle flexible pipe, it is ensured that seal reliable no leakage when removing and installing.Two ends chuck, test specimen, the upper and lower surface of side template are completely covered by bolster, ensure that chuck controls within 1 DEG C with the temperature difference at concrete sample center, 4 and the template contacts up and down of concrete sample, front and back wrapped up by chuck, chuck passes through bolster temperature control, therefore, it is ensured that the outer surface of concrete sample and the temperature difference at center are within 1 DEG C.For ensureing that temperature transfer is uniform, four pieces of hollow template inside up and down of test specimen are same journey circulation fluid;PID accurately calculates control heating and refrigerating plant, it is ensured that fine cold and hot compensation, controls the flow of input template circulation fluid, makes the temperature of circulation fluid meet the various requirement of test.Template heated cooling medium uses 40% glycol water, freezing point temperature-25 DEG C.
A kind of optimization as above technical scheme, test specimen, template, chuck and partially restrained axle are wrapped in inside by described thermal environment case, adding under thermal refrigerating device, refrigeration unit, heater and air humidifying device be applied in combination, environmental cabinet can simulated atmosphere natural environment, meet test various requirement.Environmental cabinet housing uses stainless steel, internal insulation material of filling, and insulation case lid uses telpher crane handling, possesses vertical lifting and horizontally moving functions, can be according to the field condition particular design of laboratory.Axial flow blower for air circulation is installed, for the hot and cold air mix homogeneously that will enter in environmental cabinet, it is ensured that the thermograde in environment space is within ± 2 DEG C in environmental cabinet.Under axial flow blower, damping spring is installed, it is to avoid fan vibration is delivered on casing or test specimen.Heat within environmental cabinet isolation transmits to reaction frame and base, and the heat simultaneously also completely cutting off outside internally transmits, it is ensured that temperature controlled easily-controllable property, avoids the rising-heat contracting-cold impact on measurement result of plant bottom case simultaneously.
Therefore, this device is the testing equipment being widely used in the preferable high performance-price ratios of industry such as mine, mining industry, underground engineering, metallurgical construction, national defence people's air defense, universities and colleges, transportation.
Below by drawings and Examples, this utility model is described in further detail.
Accompanying drawing explanation
The structural representation of the testing machine that Fig. 1 provides for this utility model.
The structural representation of the external structure of the master trip machine in the testing machine that Fig. 2 provides for this utility model.
The structural representation of the internal structure of the master trip machine that Fig. 3 provides for this utility model.
Fig. 4 is the A portion partial enlargement structural representation of Fig. 3.
Fig. 5 is the plan structure schematic diagram removed after the case lid 22 of environmental cabinet and cope match-plate pattern 314 of master trip machine shown in Fig. 3.
Fig. 6 is the A portion partial enlargement structural representation of Fig. 5.
Fig. 7 is that displacement transducer arranges structural representation.
Fig. 8 is side template medium recycle circuit structural representation.
Fig. 9 is medium heating procedure schematic diagram.
Figure 10 is the structural representation of an embodiment of heater.
Figure 11 is the control principle drawing of this utility model concrete cracking based on true environment overall process test.
Figure 12 is another kind of control principle drawing.
Figure 13 is functional schematic of the present utility model.
Figure 14 is temperature based on true environment and concrete stress graph.
Figure 15 is the structural representation that ball pivot seat is two halves formula structure of bulb constraint axle.
Figure 16 is the structural representation of another embodiment of described displacement/deformation-sensor composition displacement/deformation detection system of perception concrete sample deformation.
Figure 17 is quartz measuring staff and extensometer combination decomposition texture schematic diagram on test specimen.
Figure 18 is quartz measuring staff and extensometer combination structural representation on test specimen.
Figure 19 is the structural representation connecting support bar on the built-in fitting and built-in fitting arranged in test specimen.
Figure 20 is the position schematic diagram accurately arranging frock in test specimen accommodation space to ensure built-in fitting.
Figure 21 is the structural representation being arranged on the displacement/deformation-sensor outside environmental cabinet.
Figure 22 is that displacement deformation tests apparatus structure schematic diagram front view.
Figure 23 is that displacement deformation tests device detent mechanism schematic diagram front view.
Figure 24 is deformation-sensor location and installation mechanism schematic diagram front view.
Detailed description of the invention
The concrete cracking overall process testing machine based on true environment that this utility model provides is as it is shown in figure 1, include an a master trip machine A and ancillary test machine B.Being additionally provided with computer D, computer D to be connected by data wire L and control system D1, this control system D1 includes:
1. master trip machine A and ancillary test machine B controls the control unit of the various actuator of true environment analog systems;
2. the control unit of the power set in the control unit i.e. loading system of the actuator controlling concrete sample loading in master trip machine A.
The data wire L of computer D is also connected with:
1. the signal output part of the temperature sensor of monitoring of environmental parameter in master trip machine A and ancillary test machine B;
2. master trip machine A and ancillary test machine B monitors the signal output part of the displacement/deformation-sensor of the displacement/deformation of concrete sample;
3. master trip machine A monitors the signal output part of the strain gauge of test specimen stress.
The major function of computer D is:
1. parameters and the Changing Pattern of parameters of true environment to be simulated are set by computer D, control the action of each performance element of simulation true environment accordingly, the ambient parameter of each sensor feedback of monitoring of environmental parameter to be accepted and control the operation of actuator accordingly by control unit;
2. the various test parameterss in test are set by computer D, such as: the monitoring time interval of displacement/deformation-sensor and strain gauge;
3. control unit is set and instructs described power set action and described displacement/deformation-sensor and the incidence relation of described strain gauge;
4. export various result of the tests in each test by the data handling system in computer D and data output system.
One computer control system, data collecting system and data including collection at least temperature, displacement/deformation and the stress being made up of aforementioned each sensor process and output system;The signal output part of each described sensor is connected with the corresponding signal input of the data handling system of computer control system and data output system, the signal input part of described data handling system and the signal output part of data output system and an actuator connects, this actuator includes the power set in loading system and the heating in air conditioner and/or chiller, consistent with the environment of adjusting ambient case and/or concrete sample accommodation space and the true environment of setting and/or start or stop described power set;Described data handling system and data output system connect and calculate concrete sample in the true environment of described simulation include restraint stress, free variable, elastic modelling quantity, deformation separate, creep at least one result exporting.
A true environment set is simulated in the actuator of the simulation true environment of setting environment on test specimen and residing for test specimen in master trip machine A and ancillary test machine B by computer D and control system D1, in this context, test specimen deformation in the environment such as different temperatures is obtained by displacement/deformation-sensor by computer D and control system D1, the loading system being set and controlled by computer D and control system D1 again applies pulling force or pressure to test specimen in master trip machine A, complete the most freely to retrain, restraint stress, elastic modelling quantity, the separation of deformation, concrete creep and the test of concrete cracking overall process, draw the various performance parameters of concrete in various simulated environments, identical test block in ancillary test machine B is in freely unconfined state, the deformation of this test block etc. can be as a comparison.
The testing machine and the test method that there is provided with regard to this utility model below are described in detail.
Fig. 2 illustrates a kind of master trip machine, and it includes base 1, arranges environmental cabinet 2 on base 1, is additionally provided with a reaction frame 4 on base 1, is additionally provided with test specimen and houses fixing device 3 (see Fig. 3, Fig. 5) in environmental cabinet 2.
As shown in Figure 3, environmental cabinet 2 includes the uncovered casing 21 in upper end and closes the case lid 22 that described upper end is uncovered, a closing space separated with surrounding is constituted, to be built up the true environment of the setting that test needs wherein by true environment analog systems with this.
Thermal environment case transmits to reaction frame and base for the heat completely cutting off inside, and the heat simultaneously also completely cutting off outside internally transmits, it is ensured that temperature controlled easily-controllable property, avoids the rising-heat contracting-cold impact on measurement result of plant bottom case simultaneously.
Environmental cabinet 2 completely cuts off the heat of inside and transmits to reaction frame 4 and base 1, and the heat simultaneously also completely cutting off outside internally transmits, it is ensured that temperature controlled easily-controllable property, avoids the rising-heat contracting-cold impact on measurement result of plant bottom case 1 simultaneously.
As shown in Figure 3 and Figure 5, described test specimen houses fixing device 3, it is arranged in this environmental cabinet 2, including fixed bolster plate 313 in the middle part of fixed chuck 311, active chuck 312, test specimen, three's split constitutes a concrete sample accommodation space 31 that upper end is uncovered or upper and lower side is the most uncovered, the shape of cross section of this accommodation space 31 is: two ends are the heads that width greater depth is shorter, and centre is the interlude that width smaller length is longer, and described head and interlude connect transition by cone section;In the range of in the middle part of described fixed chuck 311 and active chuck 312 and test specimen, splicing seams between fixed bolster plate 313 is positioned at the interlude of this accommodation space 31, the side of side template 313 and active chuck 312 leave sideshake a1, leave end clearance a2 (as shown in Figure 6) between end face and the active chuck 312 of side template 31.The shape of concrete sample accommodation space 31 is substantially equal to be the shape of test specimen C.
A kind of test specimen houses the structure of fixing device 3: fixed chuck 311 is fixedly installed on base 1, and active chuck 312 can be movably disposed on base 1 along the axis of the length direction of described concrete sample accommodation space relative to base 1;Test specimen houses fixing device 3 and also includes a cope match-plate pattern 314, and its described upper end closing described concrete sample accommodation space 31 is uncovered.The test specimen that upper and lower side is the most uncovered is housed to the example of fixing device, this accommodation space 31 sets on bottom surface a base plate i.e. lower bolster (not shown).Bolster and two side templates be thickness be 304 Stainless Molding Boards totally 4 pieces of 70mm.
In use, concrete directly can be poured on the base plate in described concrete sample accommodation space 31 formation test specimen C, it is also possible to be placed on the base plate in accommodation space 31 by the test specimen C with this test specimen accommodation space form fit made.Support seat 31-1 (see Fig. 5) is provided below at base plate.
As shown in Figure 5 and Figure 6, in order to ensure the repetitive positioning accuracy of side template 313, it is installed fixed form and uses T-slot guidance mode, at side template 313 lateral surface fixed side form slide block 313-1, the fixed T-slot in relevant position fixed block 313-2 in environmental cabinet 2, side form slide block 313-1 is slidably fixed in the T-slot on T-slot fixed block 313-2, make the side template 313 can be in the shifted laterally of the longitudinal axis being perpendicular to accommodation space 31, one screw rod 313-3 is installed on environmental cabinet sidewall, screw rod 313-3 is screwed onto on side form slide block 313-1, a fixed adjusting handle 313-4 on screw rod 313-3.Rotate adjusting handle 313-4, drive side template 313 to horizontally slip in environmental cabinet 2 along T-slot by side form slide block.
As shown in Figure 6, maximal regulated distance a1 between side template 313 side and active chuck 312 is 10mm, side template 313 can be transferred to distance laterally maximum during the demoulding.Gap a2 between side template 313 end and active chuck is 5mm, it is ensured that test specimen is side template 313 and active chuck 312 non-contravention when compression.Gapless between cope match-plate pattern 314 and lower bolster i.e. base plate and side template 313, it is ensured that test specimen C cement when making is not extruded, and the gap a2 of side template 313 end and active chuck lives with one section of copper sheet pad the thinnest when making test specimen C.
As it is shown on figure 3, also include a stripper apparatus, the bottom surface of this base plate connecting a lowering or hoisting gear, this lowering or hoisting gear connects and one ejects reducing motor 32, can eject reducing motor 32 by this and base plate is ejected accommodation space 31 and be easily removed concrete sample C.
Specifically, the demoulding uses screw mandrel ejecting structure, is arranged on the two ends bottom test specimen, sprocket wheel chain is driven to be transferred to feed screw nut by ejecting reducing motor 32, the lifting of nut rotary screw drives push rod lifting, and for being ejected by test specimen C, maximum ejects distance 150mm.At push rod and end template i.e. base plate, dust seal is installed, prevents dust and foreign material from dropping in gap.Push rod via at base plate or lower bolster uses stainless steel tube and bed die Type of Welding, it is ensured that liquid will not seepage.Test specimen needs rotary side template adjusting handle 313-4 that side template 313 is removed some gaps before ejecting.
The two ends that mould emptier is arranged on bottom test specimen drive sprocket wheel chain to be transferred to feed screw nut by reducing motor, and the lifting of nut rotary screw drives push rod lifting, for being ejected by test specimen.
Test specimen accommodation space 31 is shaped such that test specimen is shaped as bone-shaped at collet segment, has Rouno Cormer Pregrinding Wheel transition, it is ensured that test specimen ruptures in effective length.
It is arranged on the reaction frame 4 on described base 1, as shown in Fig. 2, Fig. 3, Fig. 4 and Fig. 5, reaction frame 4 includes two root post 41, fixed cross beam 42 and fine motion crossbeams 43, form a rectangle frame, column 41 and the longitudinal direction of accommodation space, namely the axis direction of concrete sample is parallel, and two crossbeams are separately fixed at the two ends of two columns.Fixed cross beam 42 is fixed on base 1, and fine motion crossbeam is arranged on base, but and does not has fixed structure between base.
The material of column 41 and sectional dimension be: ensures power that its rigidity is 5-20 times that bears the maximum strength stress of concrete and indeformable, or stiffness K is more than or equal to 2MN/mm;Further, the material of column and sectional dimension also ensure that its temperature stability is less than 10 microns for its temperature deformation when temperature is for-20-80 DEG C.
One straight-line motion mechanism is arranged on this fine motion crossbeam 43, concrete, as shown in Figure 4 and Figure 5, straight-line motion mechanism is the screw mechanism 44 that a ball screw nut component is constituted, nut 441 in screw mechanism is fixed on constraint axle 443 through floating crossbeam 43 by nut sleeve 442, constraint axle 443 is connected on the end face of active chuck 312 through the sidewall of environmental cabinet 2 so that this active chuck 312 position is fixed or moves at described axis direction;The screw rod 444 being spirally connected with nut 441 is rotatably mounted on fine motion crossbeam 43.
Constraint axle uses centralized positioning plug will to support the axis hole center of seat and the axis hole central alignment of fixed cross beam when installing, afterwards support seat is fixed, remove plug, constraint axle is installed, location mandril uses high precision digital control lathe processing, it is ensured that concentricity is within 0.01mm.Constraint axle applies pulling force or pressure loading to test specimen under servo loading system drives, and can regulate degree of restraint as required, and 0-100% constraint is adjustable.Constraint axle front end is ball head structure, and connecting ball pivot seat can be the most freely rotatable, it is to avoid during loading, test specimen is produced torsional load, bias is had fine adjustment function.Ball pivot seat is two halves formula structures with the connection of bulb, can be by adjusting screw bolt pretightening force during installation, it is ensured that bulb is very close to each other with the connection of ball seat, it is to avoid draws, press loading to produce idle running impact when switching.
As shown in figure 15 for the two halves formula ball pivot seat attachment structure between constraint axle 443A and active chuck 312.Ball pivot seat includes front ball seat 312-10 and rear ball seat 312-11, front ball seat 312-10 is fixed on the end face of active chuck 312, rear ball seat 312-11 is fixed on front ball seat 312-10 by pretension bolt 312-12, front ball seat 312-10 and rear ball seat 312-11 constitutes the spherical space accommodating constraint axle 443A end bulb, and it is front, rear ball seat coordinates reserved certain interval at plane 312-3, can be by adjusting the pretightning force size of pretension bolt 312-12 for when mounted, ensure that bulb is very close to each other with the connection sphere of ball seat, avoid drawing, pressure produces idle running impact when loading switching.
Fixed chuck, the constraint axle at active chuck and two ends all uses invar steel 4J36 to manufacture, the diameter 150mm of constraint axle, the elastic modelling quantity of invar steel is big, linear expansion coefficient is the least, mainly for the manufacture of the element varying with temperature size approximately constant in precision instrumentation, the average linear coefficient of expansion in the range of 20~100 DEG C only has 1.4x10^-6/ DEG C, it is 660mm on measuring influential part length, therefore the result impact on experiment is 0.000924mm/ DEG C, and it is basically unchanged when-80~100 DEG C, impact on control system is the least at the trial, it is easy to improve control accuracy.
Between constraint axle 443 and environmental cabinet 2, displacement/deformation-sensor 443-3 is set, specifically, constraint axle 443 arranges measurement top board 443-1, environmental cabinet 2 lateral wall arranges support seat 443-2, arranging displacement/deformation-sensor 443-3 on this support seat 443-2, the sensing part of this displacement/deformation-sensor 443-3 is against on measurement top board 443-1.Connecting strain gauge 441-1 on nut 441, sensing part thereon is against and senses stress on support seat or constraint axle 443.
This setup of displacement/deformation-sensor 443-3 can be so as not to be loaded test specimen by power set and affected and reduce accuracy of detection.This is because the fine motion crossbeam 43 in reaction frame 4 is not connected with base 1, the counter-force of power set tension and compression test specimen will not pass on base 1, and displacement/deformation-sensor 443-3 is fixed on environmental cabinet and is fixed in fact on base 1, so being unaffected.
As shown in figs. 4 and 7, displacement/deformation-sensor 443-3 is arranged on the two ends of test specimen, is arranged symmetrically, respectively as the same in 2 precision ± 1, tunnel μm, same ancillary test B machine.Master trip seat in the plane shifting/deformation-sensor scope: ± 100 μm, ancillary test seat in the plane shifting/deformation-sensor scope: ± 2000 μm.
Supporting seat 443-2 to be arranged on base 1, when laboratory ambient temperature is constant, displacement/deformation-sensor measurement end is fixed the relative position of end and will not be changed with test specimen, the most error free.
Specific to a specific embodiment, described constraint axle 443, active chuck 312 and fixed chuck 311 all use the invar steel of high rigidity, and this material linear expansion coefficient is minimum is only (-20-100 DEG C) 1.4x10-6/ DEG C, the impact on whole device is only 0.000924mm/ DEG C, can deduct this error in experimental result, and result is more accurate;Active chuck 312 below and uses high accuracy railroad between base 1, ensured measuring accuracy.
One loading system, including power set, these power set are arranged on described reaction frame 4, concrete, and power set are as shown in Figure 4, Figure 5, are arranged on fine motion crossbeam 43.Power set include that helical gear-worm and gear, speed reducing ratio reach reductor 445 and the servomotor 446 that connected of reductor of 650, and these power set are controlled by the Loading Control unit that computer connects so that it is start and stop and limiting it to turn to.And Loading Control unit is the signal sent according to set displacement/deformation-sensor and strain gauge, controls the startup of servomotor 446 according to the requirement of concrete test and stop isoparametric.
The pitch of the screw rod 444 being spirally connected with nut 441 is 12mm.So straight-line motion mechanism, individual pulse displacement is only 0.007 μm, servomotor band closed loop feedback, substantially increases and add unloading precision, even if threshold value is arranged on 1 μm and also can easily tackle.
The preferred servomotor of described power set, connects worm reduction gear drive mechanism.Such power set make the big raising of control accuracy, feedback speed, efficiency.
Because doing long term creep strain test (loading force is constant) with this testing machine, using full servomotor Hardened gear face worm reduction gear type of drive, the accuracy controlled than motor loading stress is greatly improved.In experimentation, concrete deformation is the least, and servomotor 446 and reductor 445 match uses, and servomotor 446 speed is stepless adjustable, and loading step-length can arbitrarily select, therefore Bit andits control accuracy is higher than motor;Kind of drive ball-screw, higher than common leading screw precision, transmission efficiency the most much higher (95%), transmission uses rolling friction, and service life is long.
Tension and compression charger is made up of servomotor, helical gear-worm gear speed reducer and high-accuracy ball screw nut component, load driver device uses driven by servomotor, high-accuracy helical gear-worm gear speed reducer speed reducing ratio reaches 650, after coordinating with the ball screw that pitch is 12mm, individual pulse displacement is only 0.007 μm, servomotor band closed loop feedback, substantially increases and adds unloading precision, even if threshold value is arranged on 1 μm and also can easily tackle.
Displacement transducer and force transducer are arranged on the end of test specimen active chuck, it is simple to SERVO CONTROL is measured.Moving because of reaction frame floating end during loading, and fixing end is motionless with test specimen fixed reference end, displacement sensor top board is fixing with test specimen holds relative position motionless, so measurement error will not be introduced.
Described reaction frame 4 uses 45 steel makings, is designed to the attachment structure of the fine motion crossbeam floated in fixed cross beam one end, one end, and when stress, its deformation will not produce interference to displacement measurement, will not introduce measurement error.
Because of the reaction frame i.e. fine motion cross beam movement of the most described framework floating end during loading, and fixing end i.e. fixed cross beam is motionless with test specimen fixed reference end, and it is motionless, so measurement error will not be introduced with the relative position of the fixing end of test specimen that displacement/deformation-sensor measures top board.
Frame structure uses upright post cross-beam type, weight about 4 tons, is adapted to the rigidity requirement of long term creep strain test requirements document testing machine itself, (stiffness K >=2MN/mm).
Specifically, when loading frame bears 200KN load, maximum stress point is about 60MPa, is far smaller than material yield strength and tensile strength.When loading frame bears 200KN load, in framework, fixed cross beam and fine motion crossbeam bend laterally, two heel posts elongate and owing to the effect of moment of flexure curves inwardly, axially total deformation is 0.04655+0.04670=0.09325mm, and rigidity is 200000/0.09325=2144772N/mm=2.14MN/mm.When loading frame bears 200KN load, framework minimum safety factor is 6.49.
The described framework that this utility model provides, uses upright post cross-beam type, Stability Analysis of Structures, and column the most therein has enough rigidity and temperature deformation stability, can the precision of guarantee test well.
The constraint axle 443 at fixed chuck 311, active chuck 312 and two ends all uses invar steel 4J36 to manufacture, the diameter 150mm of constraint axle 443, the elastic modelling quantity of invar steel is big, linear expansion coefficient is the least, the average linear coefficient of expansion in the range of 20-100 DEG C only has 1.4x10^-6/ DEG C, it is 660mm on measuring influential part length, therefore the result impact on experiment is 0.000924mm/ DEG C, and it is basically unchanged when-80-100 DEG C, can calculate experimental result impact or measure, measurement result is more accurate.
On the described case lid of described environmental cabinet, form is set so that process of the test visualizes.
Figure 11 gives the control principle drawing of concrete cracking overall process based on the true environment test in an embodiment in the testing machine that this utility model provides.
As shown in figure 11, the testing machine that this utility model provides also includes computer D and control system D1, and control system D1 includes: control the control unit of true environment analog systems various actuator action in master trip machine A and ancillary test machine B;And, the control unit of the power set in the control unit i.e. loading system of the actuator action controlling concrete sample loading in master trip machine A.
Described computer D is connected with control system D1 by data wire L, meanwhile, computer D is connected also by the signal output part of data wire L and the temperature sensor of monitoring of environmental parameter, the signal output part of the displacement/deformation-sensor of monitoring concrete sample displacement/deformation, the signal output part of strain gauge of monitoring test specimen stress;
The control signal outfan of described control system D1 is connected with the control end of each actuator.
The control unit of described each actuator includes: temperature control unit, displacement/deformation control unit and Loading Control unit, computer D provides instruction, control system D1 controls each actuator action i.e.: be heated or cooled, load maintainer action is with direction initialization load or unload, allow test specimen C Free Transform or controllably deform, and initial, the direction of action of actuator action and stopping are controlled by computer D and accept the signal of displacement/deformation-sensor and the instruction that sends Loading Control System.Data handling system in computer D carries out data process for the information obtained from each sensor according to concrete test, calculates test structure and/or draws out parameter curve output.
Have in the environmental cabinet 2 that temperature control unit controls and test specimen houses the heating or cooling device in fixing device 3 and can be, cavity is set inside the accommodating fixed chuck 311 of fixing device of composition, active chuck 312 and side template 313, is passed through in cavity adds thermal medium or cooling medium by this cavity and extraneous connecting line.As a example by a side template 313, as shown in Figure 8, arranging water conservancy diversion grid in the internal cavities of side template 313, form tortuous flow path, internal diversion grid simultaneously works as reinforcement effect, it is ensured that indeformable after adding unloading test for a long time.And for example cope match-plate pattern 314 is also such structure, as it is shown on figure 3, this cavity at one end arranges medium inlet 313-5, arranges media outlet 313-6 at the other end.Medium inlet and outlet connect medium heating or cooling device, as shown in Figure 9 and Figure 10.Adapter 313-5 on the medium inlet of side template 313 connects the outlet of a pump 313-7, the inlet connection of pump 313-7 connects the outlet of a calorstat 313-8, is provided with refrigerator pipes 313-9, connects refrigerating plant, compressor refrigerant in refrigerating plant uses R502 nontoxic, environmentally safe.In calorstat 313-8, set heated cooling medium use 40% glycol water, freezing point temperature-25 DEG C.The entrance of calorstat 313-8 connects the medium outlet of side template 313.The inlet tube of pump 313-7 arranges heating coil 313-10.
Heating/cooling device as shown in Figure 9, according to test need to side template, cope match-plate pattern to such an extent as in the cavity of tank wall in fixed chuck, active chuck or even environmental cabinet 2 etc. conveying add thermal medium or cooling medium.Pump 313-7 in this heating or cooling device, the refrigerating plant connecting refrigerator pipes 313-9 and heating coil 313-10 are actuator, and it is controlled by computer D the temperature parameter set.In order to simplify the structure of computer, it is also possible to being separated from computer D whole or in part by temperature control unit, its flow chart just can become Figure 12 from Figure 11.
The heating system of heating coil 313-10 is as shown in Figure 10, add jointing temp sensor a on the inlet tube 313-12 on heat pipe i.e. pump 313-7, the signal output part of this temperature sensor a connects the signal input output end of temperature controller b, the temperature data transmission end of this temperature controller b connects the corresponding signal IO end of heating controller c, the temperature data transmitted according to temperature controller b, heating controller c exports voltage, the electric current being suitable for heating coil 313-10, make to heat coil 313-10 heating, externally embody design temperature, it is provided that the simulation of the true environment of setting.
If low temperature to be provided, heater stop works, chiller starts, circulating refrigerant in refrigerator pipes 313-9, medium d glycol water in cooling calorstat, pump 313-7 works, and carries cooling medium, it is also possible to carry in the heat exchanger simultaneously arranged in environmental cabinet in the cavity of fixed chuck, active chuck and side template.Pump 313-7 is temperature controlled the control of unit as actuator, its startup and stopping and rotating speed, it is provided that required temperature.
Fixed chuck 311, active chuck 312 and side template 313 are internal arranges cavity, in the test specimen temperature template wrap up test specimen.
In order to measure the temperature of test specimen, can temperature sensor be plugged in test specimen, the general temperature sensor by monitoring test specimen is plugged at the axial line of test specimen.To this end, all can have template thermometer hole 1 on side template 313 and each template such as fixed chuck and active chuck, in embodiment as shown in Figure 1, side template sets a thermometer hole 313-11.Cope match-plate pattern 314-1 is separately disposed with three test specimen thermometer hole 314-2, and for temperature sensor is inserted to test specimen C inside or surface, temperature sensor is distributed at piece lengths 1/4,1/2 and 3/4.
In another embodiment, described Measurement and Control System includes load sensor, displacement transducer (LVDT or grating displacement sensor), rock deformation sensor (rock extensometer), digital multichannel closed loop controller, for test specimen deformation itself is tested with stress, and drive servo to add uninstalling system test specimen adds unloading (push-and-pull), and use online with microcomputer.
Described displacement/the deformation-sensor of perception concrete sample deformation constitutes displacement/deformation detection system, and this displacement/deformation detection system is:
As shown in Figure 16, Figure 17 to Figure 19, including the rock deformation sensor being arranged in environmental cabinet 2 and two the built-in fitting C-1, fixed support bar C-0 on two built-in fittings that are arranged in test specimen.
The built-in fitting C-1 arranged in test specimen for fixed displacement/deformation-sensor, it includes the inlet part being arranged in test specimen concrete, exposes the disk body on concrete sample surface and deck, described inlet part is a plate body, the plate face of this plate body is perpendicular to the described axis of described concrete sample accommodation space, the card of the disk body being connected with inlet part is vertical with the plate body plate face of described inlet part, arranges deck with the support bar C-0 of the quartzy measuring staff being connected described temperature sensor and constitute coupling clamping structure (see Figure 19) on this disk body
Support bar C-0 passes the elongated hole on cope match-plate pattern 314, two support bar C-0 arrange quartz measuring staff C-2, this quartz measuring staff C-2 one end is fixed with the C-0 near fixed chuck side, the other end is positioned close on the support bar C-0 of active chuck 312 side and can slide axially along test specimen by this support bar C-0 relatively, described quartz measuring staff C-2 is corresponding with rock deformation sensor, with the displacement by rock deformation sensor measurement quartz measuring staff, directly measure the deflection of test specimen;
Described rock deformation sensor includes strain-type rock extensometer C-3, this extensometer C-3 with the counter structure of quartz measuring staff C-2 is: in the end of the quartzy measuring staff C-2 near active chuck 312 side, axially two contacts connectors are set on quartz measuring staff along quartz measuring staff, a contact adaptor C-2-1 by measuring staff termination is slidingly disposed on quartz measuring staff, but it is connected with support bar C-0, somewhat affixed with quartz measuring staff by more inner contact adaptor C-2-2.Two groups of chucks of extensometer C-3, one of which chuck C-3-1 contacts with contact adaptor C-2-1, and another group chuck C-3-2 contacts with contact adaptor C-2-2.Along with the force of constraint axle 443, test specimen deforms, and can be measured corresponding electricity by extensometer, then by data collecting system, this electricity is converted into dimensional values.This conversion method is prior art.
Because extensometer is output as analog quantity, range be the extensometer of 2.5mm with 24 A/D (effective code 180,000) of controller with the use of, minimum resolution is 0.014 μm, and control accuracy can 0.125 μm.
Therefore, the test piece deformation test device that this utility model provides can reach micron-sized certainty of measurement.
Displacement measuring staff all uses quartz material with deformation measuring staff, the average linear coefficient of expansion of quartz is only α 1 (-20~200 DEG C)≤0.55 × 10^-6/ DEG C, on measuring, impact is the least, it is 900mm that test piece deformation measures the centre distance of point, calculating by the linear expansion coefficient of quartz, during deformation measurement, measuring staff is acted upon by temperature changes as 0.000495mm/ DEG C, and this influence value is basically unchanged, can be by the deduction impact of this value in process of the test, it is also possible to deduct in process of the test by demarcating mode.
Noted earlier is to arrange displacement/deformation-sensor in environmental cabinet 2, additionally, as shown in figure 21, displacement/deformation-sensor can also be located at the outside of environmental cabinet 2, such as, use LVDT sensor (differential transformer sensor), lateral connection one leading-off rods C-4 on the support bar C-0 connected on two built-in fittings in test specimen C, it stretches out environmental cabinet 2, connects quartz measuring staff C-2 between two leading-off rods C-4.Quartz one end of measuring staff C-2 is fixed with the leading-off rods of fixed chuck 311 side, is movably connected with the leading-off rods of active chuck 312 side.Concrete attachment structure is: fix the iron core C-5 of LVDT transformator in the termination of quartz measuring staff C-2, termination fixed coil C-6 at leading-off rods C-4, after test specimen C stress, there is relative motion between iron core C-5 and coil C-6, thus cause the change of voltage and react the deflection of test specimen.Certainly, being arranged on the sensor outside environmental cabinet 2 can also be extensometer.Can also is that other deformation-sensor.It is arranged on the sensor ratio outside environmental cabinet 2 more directly perceived, it is easy to observation.When certainty of measurement be not required the highest in the case of, it is possible to use this external sensor.In order to avoid causing the sinking of quartz measuring staff because leading-off rods is longer, measuring staff can be set and support seat C-7.
In order to obtain more accurate data, support bar can stretch out leading-off rods to the two of environmental cabinet sidewalls, two set displacements/deformation-sensor is set.
Displacement/deformation-sensor in environmental cabinet and the displacement/deformation-sensor outside environmental cabinet can individually use, it is also possible to use simultaneously, are compared check and correction with this.
Can also be arranged on outside test specimen environmental cabinet with the grating sensor (resolution 0.1 μm) of displacement measurement, be connected with each other with active chuck 312, do not affected by internal high temperature, test piece deformation is measured and is used strain-type rock extensometer mode.
In process of the test, test piece deformation is by being embedded in the built-in fitting within test specimen, support bar is driven to move with quartz measuring staff, measuring staff one end is fixed with support bar relatively, the other end can slide axially along test specimen with relative support bar, measured the relative displacement of two support bars by extensometer, can directly measure the deflection of test specimen.Sensor accuracy is up to precision 0.1%FS (0.1 μ ε), uses temperature range-70 DEG C~180 DEG C.
The built-in fitting arranged in test specimen for fixed displacement/deformation-sensor, it includes the inlet part being arranged in test specimen concrete, exposes the disk body on concrete sample surface and deck (see Figure 19), described inlet part is a plate body, the plate face of this plate body is perpendicular to the described axis of described concrete sample accommodation space, the card of the disk body being connected with inlet part is vertical with the plate body plate face of described inlet part, arranges deck and the support bar of the quartzy measuring staff being connected described temperature sensor composition coupling clamping structure on this disk body.
In order to ensure that built-in fitting is Tong Bu with test piece deformation, built-in fitting makes flat, and big with cements face vertically, vertical direction has a disk, it is ensured that built-in fitting does not have sinking before test specimen solidifies.Built-in fitting is arranged on the axis of test specimen by positioning tool, to ensure the deformation the measured homogeneous deformation as test specimen.
So that the position of the built-in fitting being arranged in test specimen C is accurate, ensure the consistent of sample dimensions specification, can be by I-shaped frock C-8 (as shown in figure 20), its two ends are fixed on fixed chuck 311 and active chuck 312, need, by 4 alignment pins, chuck and lower bolster to be fixed together by the dowel hole of chuck both sides before filler.Apertured on the rod member in the middle of frock, detachably the fixing support bar connecting built-in fitting, then pours into a mould concrete, is fixed by built-in fitting, then remove this I-shaped part C-8.
Specifically, deformation measurement built-in fitting, after filler, inside the front cuttage of vibration to test specimen, and is installed support bar, is fixed on test specimen by positioning tooling fixture.Positioning tool can ensure that test specimen will not be subjected to displacement in vibration processes, and ensures to measure the concordance of distance.
Vibration complete after by template and test specimen integral hoisting to device interior, two ends chuck is connected with firmly with ball strand, then positioning tool, alignment pin are removed, by Figure 21 order, cope match-plate pattern, quartz measuring staff, extensometer are respectively mounted (for ensureing locating effect, it is proposed that remove frock after 3 hours).With the spike of diameter 8mm along cope match-plate pattern thermometric via, cuttage aperture on test specimen, and putting into plastic tube and cut off, temperature sensor injects test specimen by cope match-plate pattern thermometer hole along plastic tube.
Cope match-plate pattern handle 314-2 it is provided with on cope match-plate pattern.
Cope match-plate pattern placing flat, above test specimen, can freely remove and install, and circulation fluid junction medium inlet 313-5 and media outlet 313-6 uses hose connection, need not dismantle flexible pipe, it is ensured that seal reliable no leakage when removing and installing.
For ensureing that temperature transfer is uniform, the lattice structure within template, limit the liquid nowed forming in inside, four pieces of hollow template inside up and down of test specimen are same journey circulation fluid;PID accurately calculates control heating and refrigerating plant, it is ensured that fine cold and hot compensation, controls the flow of input template circulation fluid, makes the temperature of circulation fluid meet the various requirement of test.
The temperature making environmental cabinet meets the various requirement of test.Environmental cabinet housing uses stainless steel, internal filling insulation material, seals tight without deformation, and thickness is 150mm.
Test specimen, template, chuck and partially restrained axle are wrapped in inside by thermal environment case.
In addition to containing refrigeration unit, heater, it is also possible to include air humidifying device i.e. humidifier, rainer i.e. spray equipment, air flow system i.e. fan assembly, its schematic diagram is as shown in figure 12.
True environment analog systems also includes solar radiation device i.e. bulb.
Simulated atmosphere natural environment, above-mentioned each device is arranged in environmental cabinet, and such as, apertured on the tank wall of environmental cabinet 2, connecting line, the connection of this pipeline is supplied gas, sent at least one in vapour, air-supply and water injector.Apertured on the tank wall of described environmental cabinet, arranges the light fixture composition solar radiation regulation system that simulated solar irradiates in hole.Humidity sensor, air velocity transducer and solar radiation sensor are set in environmental cabinet.
Accordingly, in order to simulate true environment, in addition to temperature control unit, it is also provided with humidity controlling unit and controls the keying of humidifier or add wet strength;Rainfall control unit is set and controls keying and the flow of spray equipment;Blast velocity control unit is set and controls keying and the rotating speed of fan, solar radiation device control units is set and controls keying and the brightness of bulb.These control device and can also be simultaneously located in ancillary test machine B.
The control unit of above-mentioned actuator can be included in control system D1, and its flow chart is as is illustrated by figs. 11 and 12.
If the simulation of solar radiation to be increased, can perforate on environmental cabinet, bulb is set.
Each control unit is described as follows as a example by solar radiation with the incidence relation of computer D: the switch of bulb is actuator, correspondingly, solar radiation sensor is set in environmental cabinet, in control system D1 or be separately provided solar radiation control unit association switch, this solar radiation control unit is controlled by again in computer D the true environment parameter set and performs the operation such as closed and disconnected and strong and weak regulation.
The comparing result that computer D gathers with related sensor according to the parameters of the true environment analog systems set, instructs to each control unit, or starts or stops each actuator or adjust its degree.Thus, various true environment can be simulated in environmental cabinet, allow the various tests of test specimen carry out in specific environment.
Computer D includes temperature sensor, displacement/deformation-sensor and the information of strain gauge by collection, test function as shown in fig. 13 that can be carried out: restraint stress, free variable, elastic modelling quantity, deformation separation and concrete creep, if test block is directly to be cast in testing machine by concrete, it is possible to carry out from test and the evaluation being solidified to cracking overall process for concrete.
In this utility model, climate control system main in simulation true environment system, can there be two parts, a part is to arrange on environment casing, and another part houses at test specimen and arranges in fixing device.Environmental cabinet is arranged, is more the temperature in simulation true environment, and houses at test specimen and arrange in fixing device, the temperature of such as concrete dam in true environment can be simulated at short notice.Testing machine of the prior art does not all have the most comprehensively climate control system.
In this utility model, directly concrete can be cast in the concrete sample accommodation space that test specimen houses fixing device, so, just can test concrete in the true environment of simulation from lean state to solidification again to dilatancy and the change of stress of hardening overall process, such test can be carried out testing from pouring, be solidified to the stress of hardening overall process, strain for such as dam under difficult environmental conditions, obtain comprehensive data, for design, the information of construction offer preciousness of dam.Testing machine of the prior art does not all expect the test yet not accomplishing this overall process.Certainly, the test specimen in the testing machine that this utility model provides houses fixing device and can also test the concrete sample made.
As shown in Figure 1, ancillary test machine F in the testing machine that this utility model provides, including an environmental cabinet, i.e. include that a test specimen containing cavity is for placing the test specimen identical with the test specimen of test in described master trip machine, as an embodiment, this test specimen containing cavity arranges described temperature-adjusting device, is also provided with humidity control apparatus, solar radiation adjusting means, rainfall adjusting means and wind-speed adjusting device;This test specimen containing cavity arranges temperature sensor, also set up humidity sensor, solar radiation sensor, rainfall sensor and air velocity transducer, each described sensor is connected with described computer, and this control system D1 connects described adjusting means and regulates described test specimen to house the cavity environment parameter identical with described master trip environmental cabinet;This test specimen containing cavity also sets up the deformation with perception test specimen of the displacement/deformation-sensor.
Ambient parameter in ancillary test case is identical with master trip case, it is provided with a bottom surface placing test specimen, make the test specimen can Free Transform, it is provided with true environment analog systems, this analog systems at least includes a gas temperature controlling system, and it is provided in the heating or cooling device in described environmental cabinet and/or on test specimen;Also including temperature sensor and displacement/deformation-sensor, described temperature sensor is arranged on described test specimen and/or in environmental cabinet;Described displacement/deformation-sensor is arranged on test specimen, identical with master trip case;Each described sensor signal output part be associated with computer.
Ancillary test machine and under the conditions of test specimen and machine bed plate coefficient of friction are sufficiently small, measures and master trip the machine Free Transform of auxiliary test specimen, synthermal condition parallel test machine under the conditions of synthermal, makes test data possess integrity.
Described computer controls and parameter and control signal are transferred to measure TT&C system by processing system, measure TT&C system according to above-mentioned parameter and control signal controlled loading device, described charger according to pulling force, test specimen is loaded by displacement control signal, heating refrigeration system controls according to computer and the parameter request of processing system, test specimen is heated or freezes to uniform temperature, test specimen under tension is also deformed value, pass through pulling force, displacement transducer gathers relevant parameter and feeds back to the closed loop measurement and control instrument in described Measurement and Control System, described closed loop measurement and control instrument controls being transferred to computer after amplified for the parameter collected process and processing system 5, and by display show and printer print final result.
The testing machine that this utility model provides, concrete cracking overall process testing machine based on true environment and method realized in the following manner:
(1) under the conditions of concrete test test specimen completes and relevant device is ready to complete, start computer control system i.e. computer, carry out relative parameters setting;Open true environment analog systems, fill in the parameters such as the on-site monthly mean temperature of engineering, water temperature, cloud amount, fine day solar radiant heat, cloud amount, latitude and concrete surface exothermic coefficient, need to start the simulation of Related Environmental Factors, ambient temperature/humidity/rainfall/wind speed/solar radiation according to test;
(2) computer records the temperature of concrete according to each sensor, displacement and deformation, draw the concrete free variable under true environment simulated conditions, the concrete operations measuring Free Transform may is that test specimen is fixed between fixed chuck and active chuck, change due to temperature etc., when there is expansion or shrinkage in test specimen, the strain gauge arranged i.e. demonstrates stress value, control system i.e. starts power set, straight-line motion mechanism is made to move until strain gauge display stress value is zero in the direction that deformation direction is identical, Free Transform amount now is obtained from displacement/deformation-sensor, surveying free variable is concrete various deformation (temperature deformation, autogenous volumetric deformation and creep) carry out separation and make preparation;
(3) by computer, control system such as temperature control unit, displacement/deformation control unit, Loading Control unit and respective sensor, the Free Transform of test specimen movable terminal is controlled, the deformation reduced according to Free Transform and control, the concrete temperature stress in the case of each moment difference degree of restraint under true environment simulated conditions can be recorded, stress when being reduced to zero including making displacement, i.e. temperature stress under the conditions of staff cultivation;
(4) by computer, control system such as temperature control unit, displacement/deformation control unit, Loading Control unit and respective sensor, the Free Transform of test specimen movable terminal is carried out a secondary control, every certain time interval, displacement/deformation is made and once changes, gather corresponding STRESS VARIATION simultaneously, drawing the elastic modelling quantity in this moment, the most repeatedly, under available true environment simulated conditions, concrete is at the elastic modelling quantity of whole evolution;
(5) change in temperature Δ T (t) obtained according to thermal expansion coefficient of concrete α and data collecting system, the pure temperature deformation of concrete under true environment simulated conditions can be drawn, in conjunction with the Free Transform recorded, can show that other deform, mainly include autogenous volumetric deformation and dry-shrinkage deformed;
(6) according to the modulus of elasticity of concrete recorded and Free Transform, can calculate under true environment simulated conditions not by concrete stress during Creep Effect, start computer control system, displacement/deformation control unit, Loading Control unit and corresponding sensor, concrete deformation is controlled, be morphed into zero, at this moment record stress and not by the difference of stress during Creep Effect then for the stress caused of creeping under true environment simulated conditions;
(7) data handling system is started, in conjunction with all test datas and data and curves, when occurring, on stress and displacement curve, sudden change occurs, represent concrete cracking, the associated temperature of the concrete in this moment, stress, displacement and deformation parameter can provide test reference as the cracking index under the conditions of real-world temperature for crack-resistant performance of concrete evaluation.
The described concrete operations that freely retrain are: the two ends of concrete sample are clamped by testing machine, one end is fixed, one end can control mobile, under true environment simulated conditions, concrete can be controlled end and be not added with load, by setting computer control system, displacement/Deformation control system and the loading system of time interval (t) so that it is free displacement is μ (t), is free variable ε (t) of t concrete.
The concrete operations of described restraint stress are: the two ends of concrete sample are clamped by testing machine, one end is fixed, one end can control mobile, under true environment simulated conditions, the free displacement of concrete sample movable terminal is μ (t), according to actual needs, by computer control system, displacement/deformation control unit and loading system, displacement to test specimen movable terminal reduces, and the most described strain gauge records concrete temperature stress σ (t) in the case of each moment difference degree of restraint is constraint factor f (t);
The displacement that movable terminal reduces is:
f(t)×μ(t) (6)
In formula, t is the time, and f (t) is concrete constraint factor during t, and μ (t) is the free displacement of concrete sample movable terminal.
Described elastic modelling quantity concrete operations are: specifically, computer control system sets interval, every time interval, by displacement control system, test specimen movable terminal done a change in displacement, measure, according to strain gauge, the STRESS VARIATION that this change in displacement causes, this test specimen is carried out elasticity modulus test.
Every the △ t time, by displacement/Deformation control system, movable terminal done by test specimen and loading system change in displacement Δ μ (t), draw deformation Δ ε (t), the STRESS VARIATION amount measured according to strain gauge is Δ σ (t), then the modulus of elasticity of concrete of t is:
E ( t ) = Δ σ ( t ) Δ ϵ ( t ) - - - ( 7 )
According to the time interval of design, computer control system is automatically measured modulus of elasticity of concrete the most in the same time, i.e. be can get the concrete elastic modelling quantity in whole evolution.
The separation concrete operations of described deformation are: first do free constraint: concrete sample one end is fixed by testing machine, other end retractable, the true environment set is provided by true environment analog systems, this test specimen is carried out free variable test, in the time zone (t) set, set period collection deflection ε (t).
After 1 day age of concrete, its thermal coefficient of expansion would not change substantially again, it is considered that being a constant, this parameter can also be recorded by special thermal coefficient of expansion tester, here it is considered that it is constant α.Change in temperature Δ T (t) recorded according to thermal expansion coefficient of concrete α and temperature control system, it can be deduced that the temperature deformation of concrete under true environment simulated conditions:
ΔεT(t)=α Δ T (t) (8)
In conjunction with Free Transform ε (t) recorded, separate, can show that other deform Δ εaT (), mainly includes autogenous volumetric deformation and dry-shrinkage deformed:
Δεa(t)=ε (t)-Δ εT(t) (9)
Described concrete creep concrete operations are: according to modulus of elasticity of concrete E (t) recorded and Free Transform ε (t), can calculate under true environment simulated conditions not by concrete stress σ (t) during Creep Effect:
σ (t)=ε (t) E (t) (10)
Starting concrete displacement control system, be controlled concrete deformation so that it is be deformed into zero, at this moment recording stress is σ0(t), then the stress caused of creeping under true environment simulated conditions is reduced to:
σc(t)=σ (t)-σ0(t) (11)
Pass through σcT the size of () can draw the influence degree of concrete creep, wherein t is the time.
The concrete operations of described concrete cracking overall process are: concrete temperature changes to design temperature from initial temperature, test specimen two ends are fixed or apply pulling force, when tension data reduce suddenly, displacement increases suddenly, corresponding time m-stress, time m-deformation/displacement curve on sudden change occurs time, concrete cracking, obtain the relevant parameter of at this moment concrete, including temperature, tensile strength, limit stretch value.
The concrete operations evaluated are: combine test data and the result of above A, B, C, D, E, concrete temperature changes to setting degree, when tension data reduce suddenly, displacement increases suddenly, sudden change occurs on homologous thread time, concrete cracking, at this moment relevant parameter temperature, stress, displacement and the deformation of concrete can carry out concrete cracking overall process evaluation as to this test specimen.
Can set with the following method for true environment:
1. ambient temperature
Depending on local situation, i.e. simulation true environment is local, and above monthly mean temperature data fits to a cosine curve, and following formula (1) is the computing formula after matching:
T a = T a m + A a c o s [ π 6 ( τ - τ 0 ) ] - - - ( 1 )
In formula, TaFor temperature, TamFor average temperature of the whole year, AaFor temperature year luffing, τ is time (moon), τ0Time (moon) for maximum temperature.
Consider temperature diurnal variation, use following formula to calculate:
T a d = T a + A c o s [ π 12 ( t - 14 ) ] - - - ( 2 )
In formula,For daily temperature, TaFor monthly mean temperature, A is temperature diurnal variation amplitude, t be moment in 1 day (time) according to the Various Seasonal of different regions depending on.
2. solar radiant heat
Concrete structure is often exposed under solar radiation, and concrete temperature is had a major impact by it.The heat that in unit interval, solar radiation comes in unit are is S, wherein sets the part absorbed by concrete and is reflected as R, remainder, then:
R=αs·S (3)
In formula, αsFor absorptance, also referred to as coefficient of blackness, concrete surface typically takes 0.65.
S=S0(1-kn) (4)
In formula, S0For fine day solar radiant heat, n is cloud amount, and k is coefficient, and these three numerical value is given by local weather station;
The impact at sunshine is equivalent to the temperature of surrounding air and increases Δ Ta,
ΔTa=R/ β (5)
In formula, β is concrete surface exothermic coefficient, calculates according to surface roughness and wind speed.
3. rainfall
The rainfall of inquiry engineering location meteorological department, carrys out simulated rainfall by rainfall equipment and rainfall controller.
4. wind speed
The wind speed of the inquiry on-site meteorological department of engineering, threshold wind velocity analog, to draw concrete surface coefficient of heat transfer according to wind speed.
One concrete test example is as follows:
Use above-mentioned test method and testing machine that concrete test block is tested, verify concrete cracking overall process testing machine based on true environment and the effectiveness of method and reasonability.Test ambient temperature value is the temperature measured value of nearly a year of certain Practical Project, input computer, enable testing machine, experimental enviroment is made to survey temperature Change fully according to this, test is under the conditions of this ambient air temperature, the STRESS VARIATION situation of concrete test block, studies concrete cracking overall process based on true environment.
The test data drawn from test, can actual response Practical Project environment it can be seen that ambient air temperature meets the sinusoidal variations rule that engineering is actual;Reflecting real variation of stress based on the test temperature stress energy under the conditions of this ambient air temperature, with Temperature cycling fluctuation, based on the effect expanded with heat and contract with cold, ambient temperature raises, concrete compressive stress increases;Ambient temperature reduces, concrete compressive stress reduces tension and increases, and sees Figure 14.
As shown in Figure 22 to Figure 24, the temperature stress test that this utility model provides deforms another embodiment of direct measurement apparatus, including sensor base () 1, interior hexagonal flush end holding screw 2, centering fairlead 3, sleeve 4, LVDT displacement transducer 5, adjusts screw rod 6, M6 nut 7, sensor base (two) 8, quartz ampoule sleeve 9, quartz ampoule base 10, support bar 11, built-in fitting, 12, quartz measuring staff 13, deformation sensing, 14.
In order to ensure the consistent of sample dimensions specification, see Figure 20 and Figure 23, needed, by 4 location 16, fixed chuck and active chuck and lower bolster to be fixed together by the dowel hole of both sides before concrete fill is contained in accommodation space.After built-in fitting 12 in deformation measuring device is placed in filler, inside the front cuttage of vibration to test specimen, and installs support bar 11, by positioning tooling fixture 15, built-in fitting 12 is fixed on test specimen 15.Positioning tool can ensure that test specimen will not be subjected to displacement in vibration processes, and ensures to measure the concordance of distance.After vibration completes, then removing positioning tool 15, alignment pin 16, installation quartz measuring staff 13, deformation-sensor 14 are respectively mounted (for ensureing locating effect, it is proposed that remove frock after 3 hours).By positioning tool 15, built-in fitting 12 determines that direct measurement apparatus is arranged on the axis of test specimen, upper end connects support bar 11, support bar is inserted in sensor holder () 1, sensor holder (one) right-hand member connects centering fairlead 3, centering fairlead 3 other end is inserted in sensor holder (two) 8, it is inserted in sleeve 4 inside centering fairlead 3 in sleeve, is inserted in LVDT displacement transducer 5, adjust screw rod 6 one and insert LVDT displacement transducer 5.Adjust screw rod 6 other end and be connected fixing by sensor holder (two) 8 with quartz measuring staff 13;At sensor holder () 1 and the middle fixed deformation sensor 14 of sensor holder (two) 8.Quartz base 10 relative motion is inserted in quartz measuring staff 13 other end, and quartz base 10 is inserted in the support bar 11 of the movement of other end.Test specimen is under the influence of by stress and variations in temperature, and a support bar 11 displacement that test specimen deforms with quartz measuring staff 13 relative motion also produces change in displacement with test specimen.The built-in fitting 12 of other end and above support bar 11 position immobilize.Support bar 11 is directly connected to use quartz measuring staff 13, on measuring, impact is the least, calculate by the linear expansion coefficient of quartz, during deformation measurement, quartz measuring staff 13 is acted upon by temperature changes as 0.000495mm/ DEG C, this influence value is basically unchanged, can be by the deduction impact of this value in process of the test, it is also possible to deduct in process of the test by demarcating mode.The electronic component that measuring cell uses the sensor internal of deformation-sensor 14 the type to measure is identical with load sensor, and therefore temperature stress test deformation direct measuring method and device can well be given when test is measured accurately, accurate result.

Claims (14)

1. a concrete cracking whole process simulation testing machine, it is characterised in that: including a master trip machine, it includes a base, is provided with on the base
One environmental cabinet, at least has four walls and upper cover, forms a space closed, separates with surrounding;
One concrete sample accommodating device, it is arranged in this environmental cabinet, including fixed bolster plate in the middle part of fixed chuck, active chuck, test specimen, three's split constitutes a concrete sample accommodation space that upper end is uncovered or upper and lower side is the most uncovered, described fixed chuck is fixedly installed in this environmental cabinet, described active chuck can be arranged movably along the axis of the length direction of described concrete sample accommodation space, and described side template is placed between fixed chuck and active chuck;
At described environmental cabinet or described environmental cabinet and concrete sample accommodation space, temperature sensor and humidity sensor are set;
One true environment analog systems, it includes at least one actuator: a temperature-adjusting device, for heating and/or heat sink, it is arranged in described environmental cabinet and concrete sample accommodating device to propose fixed true environment in temperature upper mold;
One loading system, including a reaction frame, an actuating device and one with the servomotor of reductor, described reaction frame is arranged on described base, this actuating device includes a ball-screw charger, the driven member connection constraints axle that leading screw is for linear motion is connected on this charger, this constraint axle is connected with described active chuck by the sidewall entrance environmental cabinet of described environmental cabinet and this active chuck position is fixed or moves at described axis direction, and the driving link leading screw in this charger is fixed on this reaction frame;Described servomotor is arranged on described reaction frame, connects described leading screw;This servomotor constitutes load and execution mechanism, and described reductor is worm reduction gear, and described constraint axle uses invar steel making;
Described active chuck or the parts that are connected with active chuck arrange the deformation of displacement/deformation-sensor perception concrete sample;
Described ballscrew charger arranges the load that strain gauge perception test specimen bears;
One computer, this computer is connected by data wire and a control system, and this control system includes: control the control unit of true environment analog systems various actuator action in master trip machine;With the control unit of servomotor described in control concrete sample loading system in master trip machine;
Described computer connects also by data wire:
The signal output part of the described temperature sensor of monitoring of environmental parameter;
The signal output part of the displacement/deformation-sensor of the described displacement/deformation of monitoring concrete sample;
The signal output part of the described strain gauge of monitoring test specimen stress is connected;
The control signal outfan of described control system is connected with the control end of each actuator.
Testing machine the most according to claim 1, it is characterised in that:
Described displacement/the deformation-sensor of perception concrete sample deformation constitutes displacement/deformation detection system, and this displacement/deformation detection system is:
Including the rock deformation sensor being arranged in environmental cabinet and two built-in fittings being arranged in test specimen, built-in fitting arranges quartz measuring staff, this measuring staff one end is fixed with the built-in fitting near fixed chuck side, the other end is positioned close on the built-in fitting of active chuck side and can relatively slide axially along test specimen by this built-in fitting, described quartz measuring staff is corresponding with rock deformation sensor, with the displacement by rock deformation sensor measurement quartz measuring staff, directly measure the deflection of test specimen;And/or,
Including the extension bar installed on the sensor being arranged on outside described environmental cabinet and the built-in fitting arranged in test specimen, perforate on described environment tank wall, it is corresponding with the sensor being arranged on outside environmental cabinet that this extension bar stretches out described environmental cabinet, to measure the relative displacement of the extension bar on built-in fitting, measure test piece deformation amount;And/or,
The shape of cross section of described accommodation space is: two ends are the heads that width greater depth is shorter, and centre is the interlude that width smaller length is longer, and described head and interlude connect transition by cone section;In the range of in the middle part of described fixed chuck and active chuck and test specimen, splicing seams between fixed bolster plate is positioned at the interlude of this accommodation space;And/or, described test specimen houses fixing device and also includes a cope match-plate pattern, a lower bolster, and its described upper end closing described concrete sample accommodation space is uncovered uncovered with lower end;And/or,
Seam between described side template and described active chuck and/or fixed chuck leaves gap, this gap includes the gap between the termination of side template and described active chuck, to ensure test specimen side template and active chuck non-contravention when compression, and/or include the gap between the side of side template and fixed chuck and active chuck;And/or,
Described side template can be arranged in this environmental cabinet transverse shifting.
Testing machine the most according to claim 2, it is characterised in that:
The described rock deformation sensor being arranged in described environmental cabinet includes strain-type rock extensometer, it with the attachment structure being arranged on two built-in fittings is: arrange support bar on each described built-in fitting, it is positioned close on the support bar of active chuck side the end of the quartzy measuring staff connected, axially two contacts connectors are set on quartz measuring staff along quartz measuring staff, a contact adaptor by measuring staff termination is slidingly disposed on quartz measuring staff, it is referred to as sliding contact adaptor, but this sliding contact adaptor is connected with support bar, somewhat it is referred to as fixed contact adaptor by another more inner contact adaptor is affixed with quartz measuring staff;Two groups of chucks of described extensometer, one of which chuck contacts with sliding contact adaptor, and another group chuck contacts with fixed contact adaptor.
4. according to the testing machine described in claim 1 or 3, it is characterized in that: the structure being arranged on the sensor outside described environmental cabinet is: lateral connection one leading-off rods on the support bar connected on two built-in fittings in test specimen, it stretches out environmental cabinet, connects quartz measuring staff between two leading-off rods;Quartz one end of measuring staff is fixed with the leading-off rods of fixed chuck side, is movably connected with the leading-off rods of active chuck side;Arranging the sensor of perception displacement/deformation between leading-off rods and quartz measuring staff in active chuck side, this sensor is rock extensometer or differential transformer;And/or,
The built-in fitting arranged in test specimen for fixed displacement/deformation-sensor, it includes the inlet part being arranged in test specimen concrete, exposes the disk body on concrete sample surface and deck, described inlet part is a plate body, the plate face of this plate body is perpendicular to the described axis of described concrete sample accommodation space, the card of the disk body being connected with inlet part is vertical with the plate body plate face of described inlet part, arranges deck and the support bar of the quartzy measuring staff being connected described temperature sensor composition coupling clamping structure on this disk body;And/or,
Also including an ancillary test machine, this ancillary test machine includes that a test specimen containing cavity, for placing the test specimen identical with the test specimen of test in described master trip machine, arranges described temperature-adjusting device in this test specimen containing cavity;Arranging temperature sensor and humidity sensor in this test specimen containing cavity, each described sensor is connected with described computer, and described control system connects described adjusting means and regulates described test specimen to house the cavity environment parameter identical with described master trip machine environmental cabinet;This test specimen containing cavity also sets up the deformation with perception test specimen of the displacement/deformation-sensor;And/or,
The control unit of each described actuator includes: temperature control unit, displacement/deformation control unit and Loading Control unit;And/or,
Described control system also includes the control unit controlling the various described actuator action of true environment analog systems in described ancillary test machine.
5. according to the testing machine one of claims 1 to 3 Suo Shu, it is characterised in that:
It is arranged on the heating in the described temperature-adjusting device in described environmental cabinet and/or heat sink is:
In the space being arranged in the tank wall of described environmental cabinet or close, described tank wall has hollow chamber, and/or, described fixed chuck, active chuck and the side template at least one that test specimen houses in fixing device is set there is hollow chamber;
Each described hollow chamber arranges inlet and outlet and connects with the medium channel of described heating and/or heat sink, described actuator is the delivery pump of the electrical heating coil arranged on the medium channel of this heating and/or heat sink and/or the media flow driving heating or cooling, this medium channel connects refrigeration compressor set, for providing heat energy or cold energy the most as required.
Testing machine the most according to claim 4, it is characterised in that:
It is arranged on the heating in the described temperature-adjusting device in described environmental cabinet and/or heat sink is:
In the space being arranged in the tank wall of described environmental cabinet or close, described tank wall has hollow chamber, and/or, described fixed chuck, active chuck and the side template at least one that test specimen houses in fixing device is set there is hollow chamber;
Each described hollow chamber arranges inlet and outlet and connects with the medium channel of described heating and/or heat sink, described actuator is the delivery pump of the electrical heating coil arranged on the medium channel of this heating and/or heat sink and/or the media flow driving heating or cooling, this medium channel connects refrigeration compressor set, for providing heat energy or cold energy the most as required.
7. according to the testing machine one of claims 1 to 3 Suo Shu, it is characterized in that: the attachment structure between described constraint axle and described active chuck and/or fixed chuck is for being articulated and connected, the termination of described constraint axle is bulb, the ball pivot seat arranged on described active chuck and/or fixed chuck is two halves formula structures, described ball pivot seat includes front ball seat and rear ball seat, described front ball seat is fixed in the both ends of the surface of described fixed chuck and/or active chuck, rear ball seat is fixed on front ball seat by pretension bolt, front ball seat and rear ball seat constitute the spherical space accommodating constraint shaft end bulb, and the connection of ball pivot seat and bulb is two halves formula structures, and it is front, rear ball seat coordinates reserves a gap at plane.
Testing machine the most according to claim 5, it is characterized in that: the attachment structure between described constraint axle and described active chuck and/or fixed chuck is for being articulated and connected, the termination of described constraint axle is bulb, the ball pivot seat arranged on described active chuck and/or fixed chuck is two halves formula structures, described ball pivot seat includes front ball seat and rear ball seat, described front ball seat is fixed in the both ends of the surface of described fixed chuck and/or active chuck, rear ball seat is fixed on front ball seat by pretension bolt, front ball seat and rear ball seat constitute the spherical space accommodating constraint shaft end bulb, and the connection of ball pivot seat and bulb is two halves formula structures, and it is front, rear ball seat coordinates reserves a gap at plane.
Testing machine the most according to claim 4, it is characterized in that: the attachment structure between described constraint axle and described active chuck and/or fixed chuck is for being articulated and connected, the termination of described constraint axle is bulb, the ball pivot seat arranged on described active chuck and/or fixed chuck is two halves formula structures, described ball pivot seat includes front ball seat and rear ball seat, described front ball seat is fixed in the both ends of the surface of described fixed chuck and/or active chuck, rear ball seat is fixed on front ball seat by pretension bolt, front ball seat and rear ball seat constitute the spherical space accommodating constraint shaft end bulb, and the connection of ball pivot seat and bulb is two halves formula structures, and it is front, rear ball seat coordinates reserves a gap at plane.
Testing machine the most according to claim 5, it is characterized in that: the attachment structure between described constraint axle and described active chuck and/or fixed chuck is for being articulated and connected, the termination of described constraint axle is bulb, the ball pivot seat arranged on described active chuck and/or fixed chuck is two halves formula structures, described ball pivot seat includes front ball seat and rear ball seat, described front ball seat is fixed in the both ends of the surface of described fixed chuck and/or active chuck, rear ball seat is fixed on front ball seat by pretension bolt, front ball seat and rear ball seat constitute the spherical space accommodating constraint shaft end bulb, and the connection of ball pivot seat and bulb is two halves formula structures, and it is front, rear ball seat coordinates reserves a gap at plane.
11. testing machines according to claim 5, it is characterized in that: the attachment structure between described constraint axle and described active chuck and/or fixed chuck is for being articulated and connected, the termination of described constraint axle is bulb, the ball pivot seat arranged on described active chuck and/or fixed chuck is two halves formula structures, described ball pivot seat includes front ball seat and rear ball seat, described front ball seat is fixed in the both ends of the surface of described fixed chuck and/or active chuck, rear ball seat is fixed on front ball seat by pretension bolt, front ball seat and rear ball seat constitute the spherical space accommodating constraint shaft end bulb, and the connection of ball pivot seat and bulb is two halves formula structures, and it is front, rear ball seat coordinates reserves a gap at plane.
12. according to the testing machine one of claims 1 to 3 Suo Shu, it is characterized in that: described reaction frame is the framework of the rectangle including two crossbeams and two column compositions, one fixed cross beam is fixed on the described base of described fixed chuck side, two described columns described fixed cross beam that is connected abreast is positioned at described environmental cabinet both sides, one fine motion crossbeam is arranged on the described base of described active chuck side, it is connected with described column, described servomotor is arranged on this fine motion crossbeam, it is consequently formed reaction frame, described straight-line motion mechanism is connected through this fine motion crossbeam with active chuck, the support section of described displacement/deformation-sensor and described strain gauge is fixed on described base directly or indirectly;And/or,
In the described reaction frame that two described crossbeams and two described columns are constituted, the material of described column and sectional dimension be: ensures power that its rigidity is 5-20 times that bears the maximum strength stress of concrete and indeformable, or stiffness K is more than or equal to 2MN/mm;And/or, it is ensured that when its temperature stability is in the temperature range-20-80 DEG C of test, its temperature deformation is less than 10 microns;And/or,
Described environmental cabinet described on cover form be set so that process of the test visualizes;And/or,
A hoisting mechanism is also set up at described base, house at described test specimen and fixing device arranges a base plate for placing test specimen or pouring into a mould test specimen thereon, this base plate connects this hoisting mechanism, by running this hoisting mechanism, it is possible to by test specimen into and out concrete sample accommodation space.
13. testing machines according to claim 4, it is characterized in that: described reaction frame is the framework of the rectangle including two crossbeams and two column compositions, one fixed cross beam is fixed on the described base of described fixed chuck side, two described columns described fixed cross beam that is connected abreast is positioned at described environmental cabinet both sides, one fine motion crossbeam is arranged on the described base of described active chuck side, it is connected with described column, described servomotor is arranged on this fine motion crossbeam, it is consequently formed reaction frame, described straight-line motion mechanism is connected through this fine motion crossbeam with active chuck, the support section of described displacement/deformation-sensor and described strain gauge is fixed on described base directly or indirectly;And/or,
In the described reaction frame that two described crossbeams and two described columns are constituted, the material of described column and sectional dimension be: ensures power that its rigidity is 5-20 times that bears the maximum strength stress of concrete and indeformable, or stiffness K is more than or equal to 2MN/mm;And/or, it is ensured that when its temperature stability is in the temperature range-20-80 DEG C of test, its temperature deformation is less than 10 microns;And/or,
Described environmental cabinet described on cover form be set so that process of the test visualizes;And/or,
A hoisting mechanism is also set up at described base, house at described test specimen and fixing device arranges a base plate for placing test specimen or pouring into a mould test specimen thereon, this base plate connects this hoisting mechanism, by running this hoisting mechanism, it is possible to by test specimen into and out concrete sample accommodation space.
14. testing machines according to claim 5, it is characterized in that: described reaction frame is the framework of the rectangle including two crossbeams and two column compositions, one fixed cross beam is fixed on the described base of described fixed chuck side, two described columns described fixed cross beam that is connected abreast is positioned at described environmental cabinet both sides, one fine motion crossbeam is arranged on the described base of described active chuck side, it is connected with described column, described servomotor is arranged on this fine motion crossbeam, it is consequently formed reaction frame, described straight-line motion mechanism is connected through this fine motion crossbeam with active chuck, the support section of described displacement/deformation-sensor and described strain gauge is fixed on described base directly or indirectly;And/or,
In the described reaction frame that two described crossbeams and two described columns are constituted, the material of described column and sectional dimension be: ensures power that its rigidity is 5-20 times that bears the maximum strength stress of concrete and indeformable, or stiffness K is more than or equal to 2MN/mm;And/or, it is ensured that when its temperature stability is in the temperature range-20-80 DEG C of test, its temperature deformation is less than 10 microns;And/or,
Described environmental cabinet described on cover form be set so that process of the test visualizes;And/or,
A hoisting mechanism is also set up at described base, house at described test specimen and fixing device arranges a base plate for placing test specimen or pouring into a mould test specimen thereon, this base plate connects this hoisting mechanism, by running this hoisting mechanism, it is possible to by test specimen into and out concrete sample accommodation space.
CN201620131497.5U 2016-02-19 2016-02-19 Concrete cracking overall process emulation testing machine Withdrawn - After Issue CN205580953U (en)

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105572027A (en) * 2016-02-19 2016-05-11 中国水利水电科学研究院 Concrete cracking whole-process simulating tester
CN107894362A (en) * 2017-12-26 2018-04-10 东莞理工学院 A kind of longitudinal direction, rotational stiffness constrain certainly and self-balancing experimental rig and test method
CN107941612A (en) * 2017-11-14 2018-04-20 中国水利水电科学研究院 A kind of method for measuring concrete early stage elasticity modulus
CN108254247A (en) * 2017-12-21 2018-07-06 中国水利水电科学研究院 The apparatus and method for of single axle concrete constraint under a kind of difference curing condition
CN109541188A (en) * 2019-01-08 2019-03-29 深圳前海砼源建设科技有限公司 A kind of high-precision coagulation cracking resistance detection device
CN112345340A (en) * 2020-10-16 2021-02-09 中国地质大学(武汉) Controllable angle crack surface generation device for cylindrical rock sample
CN112650319A (en) * 2020-11-26 2021-04-13 陕西威斯特高新技术投资有限公司 Automatic temperature control equipment for building
CN113624179A (en) * 2021-07-21 2021-11-09 袁松 Different thickness steel mesh mould concrete wall contrast detects uses crack control testing arrangement
CN113984507A (en) * 2021-11-16 2022-01-28 中国石油大学(华东) Multi-station high polymer material accelerated aging test method and device considering stress-thermal oxygen coupling effect

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105572027A (en) * 2016-02-19 2016-05-11 中国水利水电科学研究院 Concrete cracking whole-process simulating tester
CN107941612A (en) * 2017-11-14 2018-04-20 中国水利水电科学研究院 A kind of method for measuring concrete early stage elasticity modulus
CN108254247A (en) * 2017-12-21 2018-07-06 中国水利水电科学研究院 The apparatus and method for of single axle concrete constraint under a kind of difference curing condition
CN108254247B (en) * 2017-12-21 2020-05-12 中国水利水电科学研究院 Device and method for single-shaft concrete constraint under different curing conditions
CN107894362B (en) * 2017-12-26 2023-09-19 东莞理工学院 Longitudinal and rotational rigidity self-restraint and self-balance test device and test method
CN107894362A (en) * 2017-12-26 2018-04-10 东莞理工学院 A kind of longitudinal direction, rotational stiffness constrain certainly and self-balancing experimental rig and test method
CN109541188A (en) * 2019-01-08 2019-03-29 深圳前海砼源建设科技有限公司 A kind of high-precision coagulation cracking resistance detection device
CN112345340A (en) * 2020-10-16 2021-02-09 中国地质大学(武汉) Controllable angle crack surface generation device for cylindrical rock sample
CN112650319B (en) * 2020-11-26 2022-04-15 陕西威斯特高新技术投资有限公司 Automatic temperature control equipment for building
CN112650319A (en) * 2020-11-26 2021-04-13 陕西威斯特高新技术投资有限公司 Automatic temperature control equipment for building
CN113624179A (en) * 2021-07-21 2021-11-09 袁松 Different thickness steel mesh mould concrete wall contrast detects uses crack control testing arrangement
CN113984507A (en) * 2021-11-16 2022-01-28 中国石油大学(华东) Multi-station high polymer material accelerated aging test method and device considering stress-thermal oxygen coupling effect
CN113984507B (en) * 2021-11-16 2023-08-04 中国石油大学(华东) Multi-station high polymer material accelerated aging test method

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