Embodiment
To make the technical problem to be solved in the present invention, technical scheme and advantage clearer, below in conjunction with accompanying drawing and tool
Body embodiment is described in detail.
The rock triaxial test equipment of the embodiment of the present invention includes:Main frame 1, motor 2, balancing gate pit 3, electro-hydraulic loading
System, functional devices, measurement control section, computer control and data handling system composition each several part are constituted and said with function
It is bright.
As shown in Figure 1 and Figure 2, wherein main frame 1 is square shape framework, and center is provided with the sky for being used for housing balancing gate pit 3
Between;Hoisting mechanism 5 and guideway up-and-down mechanism 32 are provided with the side of main frame 1.As shown in Figure 2, the balancing gate pit 3 includes cylinder 34
With base 38, the base 38 of cylinder more than 34 is removably secured together to sealed inner chamber by split type clip 39;
Seaming chuck 301 and push-down head 302 are provided with cylinder 34, seaming chuck 301 is corresponding with the position of push-down head 302 with to test specimen 4
Press axial compressive force;And the base 38 imports and exports 37 to apply radial pressure to test specimen 4 provided with confined pressure;And the cylinder 34
It is interior to be provided with Axial extensometer 303 and radial extensometer 304.As shown in Figure 3, exhaust outlet 35 is provided with the top of cylinder 34, and
Air inlet 36 is provided with push-down head 302.As shown in Figure 3, hangers 32 is provided with the top of cylinder 34, is provided with the bottom of base 38
Dowel hole 31.
As shown in Figure 1, the hoisting mechanism 5 includes support, lift cylinder, piston rod;Wherein stent side portion is fixed on master
On the side of framework 1, and lift cylinder is fixed on support, and the lift cylinder bottom is provided with the piston rod for extending support,
Piston rod bottom is removably fixedly connected provided with buckle with the hangers 32 at the top of cylinder 34 with balancing gate pit 3, with driving pressure
Move room 3.
Also include confined pressure servo loading mechanism of balancing gate pit as shown in Figure 4, with dynamic needed for providing experiment for balancing gate pit 3
Power.Confined pressure servo loading mechanism of balancing gate pit as shown in Figure 4 includes hydraulic pressure oil tank 71, oil pump 72, piston 73, balancing gate pit 74, sky
Press 75;Wherein balancing gate pit 74 can be balancing gate pit 3 as shown in Figure 3.Hydraulic pressure oil tank 71 connects balancing gate pit 74 by oil pump 72,
And air compressor machine 74 also connects balancing gate pit 74.Wherein it is used to store hydraulic oil in hydraulic pressure oil tank 71, to pass through the piston 73 of oil pump 72
Effect hydraulic oil is input in balancing gate pit 74 to provide confined pressure;And after experiment is finished by air compressor machine 75 to balancing gate pit 74
Interior pressurization is so that hydraulic oil returns to hydraulic pressure oil tank 71.Due to being likely to occur the problem of test specimen 4 produces chip in experiment, therefore in liquid
Press oil the valve and waste liquid pool that can be used to release the water containing silt provided with bottom in tank 71.
Also include gas absorption as shown in Figure 5 and measure measuring mechanism, the adsorption isothermal curve for measuring sample.Such as Fig. 5
Shown, the gas absorption, which measures measuring mechanism, to be included:Pipeline calibration buret 82, gas componant detector 83, flowmeter 84, high pressure
Gas cylinder 85, gasing tank calibration buret 86, bath of liquid pond 87, gasing tank 88, confined pressure booster 89, pressure sensor 90, manifold volume
Demarcate fixture 91, radial force snesor 92, temperature sensor 93.Wherein confined pressure booster 89 is connected by pressure sensor 90
Balancing gate pit 3 is provided with temperature sensor 93 and radial force snesor 92 to be pressurized to balancing gate pit, and in balancing gate pit 3.Wherein pressure
Room 3 is connected with loading line and blowdown piping, and loading line is provided with gasing tank 88, gasing tank calibration buret 86, gas cylinder
85;And blowdown piping is provided with pipeline calibration buret 82, gas componant detector 83, flowmeter 84;Also include connecting retractable
Connection loading line and blowdown piping vavuum pump 81.As shown in Figure 5, the gasing tank is arranged in bath of liquid pond 87, the liquid
Bathing pool 87 can be water-bath or oil bath.As shown in Figure 5, in addition to manifold volume demarcation fixture 91.
Also include high pressure displacement model pipe mechanism as shown in Figure 6 and Figure 7, high pressure displacement model pipe is tried for high pressure displacement
Test and adsorb free wxpansion body and become experiment.High pressure displacement model pipe is used for high pressure displacement test and absorption free wxpansion body becomes real
Test, to ensure that the liquid capacity in pressure change around test specimen does not change (diameter and length of model pipe are constant), from
And the precision of measurement result is influenceed, the model pipe of the embodiment of the present invention employs double-decker, internal layer pressure part and sandwich part
Partial pressure is equal, in theory because the liquid capacity variable quantity (surveyed body in model pipe caused by pressure change and become part) is zero.Examination
Part expansion causes the pressure rise in model pipe, and measuring pump, need to be by the liquid in model pipe in order to maintain the pressure of inside constant
Extract out, the liquid volume of metering pumped is free wxpansion body variable.Axial extensometer (less than 100 DEG C are applicable) measurable axle
To deflection, the average radial deflection of test specimen can be calculated by body variable and axial deflection.Model pipe and conduction oil meeting
Swelling is produced with the meeting of temperature, in the experiment of each temperature section, initial volume need to be recorded or relatively initial
Volume is reset.In order to reduce because temperature rise, cause expansion it is excessive, the pressure head of model pipe inner cylinder, support frame and test specimen two ends can
Using invar steel making, its linear expansion coefficient average value at 0-200 DEG C is only 1.8x10-6, is ordinary carbon steel (12.1-
13.5x10-6) 1/7 or so so that measurement accuracy is higher.High-precision measuring pump provides voltage stabilizing for test specimen confined pressure and body becomes survey
Amount.
As shown in Figure 5, the high pressure displacement model pipe mechanism includes the double Shell that shell 104 and inner casing 105 are constituted, and
The double Shell is provided with the interlayer pressure entrance 111 pressurizeed for interlayer;As shown in figure 5, being provided with the double Shell is used to hold
Put the heat-shrinkable T bush 107 of test specimen 4;Seaming chuck 102 and push-down head 108 are respectively equipped with the top and bottom of heat-shrinkable T bush 107.Such as
Shown in Fig. 5, gas outlet tube 106 is provided with inner casing 105, the gas outlet tube 106 connection expels gas access 109, and
The gas access 109 that expels is arranged at double Shell bottom, and the one end of gas outlet tube 106 connection expels gas access
109, the other end is extended at the top of double Shell.As shown in figure 5, being provided with steam vent 101 at the top of double Shell, bottom is provided with drive
From gas vent 110.
Also include the tracking of ring pressure and measuring mechanism as described in Figure 8, it includes high-precision differential manometer, confined pressure servo loading dress
Put, high accuracy displacement sensor.Ring pressure tracking system can realize coal sample gas liter synchronous with confined pressure liquid in reative cell heat-shrink tube
Pressure, the body adsorbed by the displacement variable and then calculating coal sample of high-precision displacement sensor pore pressure servo-loading unit
Product free wxpansion amount.As shown in Figure 7, including:Oil storage tank 201, high pressure displacement model pipe 202, confined pressure servo-loading unit
203rd, differential manometer DP2;Gas collector 204, gas-liquid separator 205, gas chromatograph 206;Wherein confined pressure servo-loading unit
203 connection high pressure displacement model pipes 202, differential manometer DP2 connection high pressure displacements model pipe 202;Its mesohigh displacement model pipe 202
The gentle collection 204 of gas-liquid separator 205 is connected, is also connected with gas chromatograph 206 to carry out the gas componant of sub-department
Analysis.
As shown in Figure 9, the rock permeation principle of the equipment of the embodiment of the present invention is:
1st, test specimen 4 is placed in balancing gate pit 3, sealed seaming chuck 301, push-down head 302 with test specimen with protective case, coal sample
Test specimen 4 wraps up heat-shrinkable T bush (or other materials) to isolate gas circuit and oil circuit;
2 and then sample 4, inlet gas are vacuumized and nominal volume with reference to tank 202, exit gas with reference to tank 201 and pipeline
Product;Then by CO after vacuumizing again2From high-pressure cylinder 203 penetrates into the hole of test specimen 4 by three-axis penetration bottom of device, high pressure
Gas is introduced into air inlet with reference to tank 202, closes air intake valve, reads differential manometer CP2 pressure differences;Test specimen intake valve is opened again
Door, CO2Enter gas outlet through test specimen 4 and refer to tank 201, by importing and exporting the pressure difference and body of gas reference tank 201 after pressure balance
Product calculates the infiltration coefficient of test specimen, and specific formula for calculation is as follows:
As shown in Figure 5, coal petrography adsorptivity experimental principle is:
1st, assay method:The drying coal sample handled well is encased in balancing gate pit, plus certain confined pressure, vacuum outgas, determines and inhales
Attached tank residual volume, the methane of certain volume is filled with into balancing gate pit so that the pressure in protective case reaches balance, portion gas
Adsorbed, portion gas is still in residual volume with free state, it is known that insufflation gas volume, deducts the episome of residual volume
Product, as adsorption volume.
2nd, free space volumes are determined:Set and regulating system temperature, make balancing gate pit and reach desirable value with reference to cylinder temperature
Open helium tank and be filled with helium to system, regulation is closed with reference to cylinder pressure value to 2-30MPa and opens balancing gate pit with reference to cylinder valve door
With refer to cylinder connecting valve, after gathering one group of data after pressure balance.
Repeat above step twice, try to achieve the volume of coal sample, and calculate the free space volumes in sample cylinder.Free space
Volume needs duplicate measurements 3 times.
The volume calculation formula of coal sample:
VS:The volume of coal sample, unit is cubic centimetre (cm3);P1:Pressure after balance, unit is MPa (MPa);P2:Ginseng
Cylinder initial pressure is examined, unit is MPa (MPa);P3:Sample cylinder initial pressure, unit is MPa (MPa);T1:Temperature after balance,
Unit is to open (K);T2:With reference to cylinder initial temperature, unit is to open (K);T3:Sample cylinder initial temperature, unit is to open (K);Vl:System
System cumulative volume, unit is cubic centimetre (cm3);V2:With reference to cylinder volume, unit is cubic centimetre (cm3);V3:Sample cylinder volume,
Unit is cubic centimetre (cm3);Z1:The compressibility factor of gas under equilibrium condition;Z2:With reference to the compressibility factor of cylinder initial gas;
Z3:The compressibility factor of sample cylinder initial gas.
The volume of coal sample is tried to achieve, free space volumes in sample cylinder are calculated.
Shown under calculation formula such as formula:
Vf-V0-Vs
In formula:Vf:Free space volumes, unit is cubic centimetre (cm3);V0:Sample cylinder cumulative volume, unit for cube li
Rice (cm3);VS:The volume of coal sample, unit is cubic centimetre (cm3)。
According to reference to cylinder, the balance pressure of balancing gate pit and temperature, the adsorbance of not homostasis pressure spot, calculation formula are calculated
For
PV=nZRT
In formula:
p:Gas pressure, unit is MPa (MPa);V:Gas volume, unit is cubic centimetre (cm3);n:Gas rubs
That number, unit is to rub (mol);Z:The compressibility factor of gas;R:Mol gas constant, unit is often rubbed out (mol) for Jiao;T:Balance
Temperature, unit is to open (K).
Each pressure spot is obtained respectively balances number of moles of gas n in preceding balancing gate pit1With number of moles of gas in balancing gate pit after balance
n2, then the molal quantity n of coal sample adsorbed gasiFor:
ni=n1-n2
In formula:ni:The molal quantity of gas, unit is to rub (mol);n1:The molal quantity of sample gas in the jar, unit before balance
For rub (mol);n2:The molal quantity of sample gas in the jar after balance, unit is to rub (mol).
Cumulative volume (the V of the adsorbed gas of each pressure spoti) see equation below:
Vi=ni×22.4×1000
Adsorbance (the V of each pressure spotAdsorbance) see equation below:
VSuction amount=Vi/Gc
In formula:VSuction amount:Suction amount, unit is every gram of cubic centimetre (cm3.g-1);Vi:Sample gas in the jar rubs before balance
That number, unit is to rub (mol);Gc:Coal sample quality, unit is gram (g).
3rd, V is calculatedLAnd PL
According to Langmuir equations:
P/V=p/VL+pL/VL
In formula:p:Gas pressure, unit is MPa (MPa);V:The suction amount under the conditions of pressure p, unit is cubic centimetre
Every gram of (cm3.g-1);VL:Maximum suction capacity, also known as Langmuir volumes, unit are every gram of cubic centimetre (cm3.g-1);pL:
Langmuir pressure, unit is MPa (MPa).
If making A=1/VLAnd B=pL/VL, can be by function of the equation inference for p/V and p:
P/V=p/VL+pL/VLOr p/V=Ap+B
According to equation, the pressure of each pressure balance point of actual measurement and suction amount data can be drawn using p as abscissa, with p/
V ratios are the scatter diagram of ordinate, and the regression beeline equation and coefficient correlation of these scatter diagrams are obtained using least square method
(R), enter hundred slopes (A) and intercept (B) for obtaining straight line, Langmuir volumes (V is obtained according to slope and interceptL) and
Langmuir pressure (pL), i.e.,:
VL=1/A
pL=B/AOr pL=VLB
Adsorption isothermal curve is drawn according to the adsorbance V and pressure p of each pressure spot.
If storage pressure limitation reference cylinder pressure can not meet requirement of experiment during experiment, it can be incited somebody to action by gas booster
Desirable value is compressed to reference to cylinder pressure to be tested again.
The pipeline for being connected to balancing gate pit is pulled down from joint and is connected with the air inlet/outlet of displacement pipe, CO is carried out2Displacement
Experiment.Now there is flowmeter (10MPa, 5sccm) at cylinder outlet end, have gas componant detector and flow in test specimen exit
Count (10MPa, 5sccm).
Coal petrography volume after adsorbed gas can expand phenomenon, in pressure axial load without and keep confined pressure not
In the case of change, test specimen can produce axial deformation and radial deformation, and three radial directions are provided with the position of test specimen upper, middle and lower three
Extensometer is deformed, three extensometer deflections are read by computer control system and averaged as the radial deformation of test specimen
Amount, axial deflection is obtained by reading Axial extensometer data.
Force sensor is installed at pressure head position above test specimen, and sensor site is connected and holding position with equipment rack
Motionless, coal petrography is delivered to force snesor in expansion to the counter-force that pressure head is produced, and computer control system reads sensing data,
And divided by test specimen area obtain because expansion produce axial stress.
The embodiment of the present invention can be summarized as follows:
1 balancing gate pit's lifting device
Balancing gate pit's lifting device is used for the lifting of balancing gate pit's cylinder when test specimen is dismounted to top, in order to install test specimen and folder
Extensometer etc. is held, there is hydraulic lift(ing) cylinder, the composition such as support and lifting part.
2 rail elevating devices
Rail elevating device is used for balancing gate pit's dolly and is dropped to bottom-loaded plate in experiment, by guide rail during turnover
It is lifted to concordant with outer rail.Mainly by fixed guide rail, moving cart, riser guide, cylinder, air cylinder support and manual reverse of direction
Valve etc. is constituted.
3 gas absorption amount test devices
Adsorption isothermal curve for measuring sample, mainly demarcates fixture, vavuum pump, pipeline calibration amount by manifold volume
Pipe, gasing tank, gasing tank calibration buret, gas booster, gas cylinder, constant temperature oil bath, temperature control instrument, pressure sensor, pipe
Road and valve composition.
4 balancing gate pit's confined pressure servo loading systems
Loading, unloading and guarantor for balancing gate pit's confined pressure are carried, servomotor ball screw structure, and confined pressure undulate quantity is small, add
Carry temperature reliable, be made up of electrical servo booster, confined pressure oil inlet and oil return device and pipeline, valve etc..
Stop valve is opened during confined pressure oil-feed, the pressurised oil in fuel tank is pumped into high-voltage oil cavity by servo confined pressure actuator, so
After close stop valve, pressurised oil is injected into balancing gate pit by servo actuator.During oil extraction, servo actuator is first unloaded, by pneumatics
Machine valve is opened, and compressed air gas enters balancing gate pit by balancing gate pit's air inlet and extrudes pressurised oil from confined pressure oil discharge outlet, supercharging
Oil is back to fuel tank precipitation, filtering, and experiment next time is injected into balancing gate pit when needing by actuator.
5 displacement model pipe cell mesh
Constituted by high pressure resistant displacement model pipe, constant temperature system, with reference to cylinder etc..Simulated formation high temperature, high pressure (confined pressure), sealing
Environment.
High pressure displacement model pipe is used for high pressure displacement test and absorption free wxpansion body becomes experiment, to ensure in pressure change
When test specimen around liquid capacity do not change (diameter and length of model pipe are constant), so as to influence the essence of measurement result
Degree, this model pipe employs double-decker, and internal layer pressure part is equal with sandwich portion pressure, in theory because pressure change causes
Model pipe in (survey body become part) liquid capacity variable quantity into zero.Test specimen expansion causes the pressure rise in model pipe, meter
Pump is measured in order to maintain the pressure of inside constant, the liquid in model pipe need to be extracted out, the liquid volume of metering pumped is certainly
By expander variable.Axial extensometer (less than 100 DEG C are applicable) measurable axial deflection, passes through body variable and axial deflection
The average radial deflection of test specimen can be calculated.
Model pipe and conduction oil can produce swelling with the meeting of temperature, need to be to first in the experiment of each temperature section
Initial body product is recorded or relative initial volume is reset.In order to reduce because of temperature rise, cause expansion excessive, model pipe inner cylinder,
Support frame and the pressure head of test specimen two ends can use invar steel making, and its linear expansion coefficient average value at 0-200 DEG C is only
1.8x10-6, is 1/7 or so of ordinary carbon steel (12.1-13.5x10-6) so that measurement accuracy is higher.
High-precision measuring pump provides voltage stabilizing for test specimen confined pressure and body becomes measurement.
The tracking of 6 rings pressure and measurement apparatus cell mesh
It is made up of high-precision differential manometer, confined pressure servo-loading unit, high-precision measuring pump etc..Ring pressure tracking system can be realized
Coal sample gas and confined pressure liquid synchronous boost in reative cell heat-shrink tube, by high-precision measuring pump measure confined pressure because keep it is constant and
The volume of the conduction oil of discharge is so as to obtain the volume free wxpansion amount of coal sample absorption.
Experimentation middle ring pressure (heat conduction oil pressure in interlayer) P1 need to be slightly larger than gas pressure P0, and gas pressure liter at any time
Height is reduced and adjusted, and confined pressure servo-loading unit presses imposed load to ring, it is ensured that differential manometer DP2 is typically set in certain value
0.1MPa is scheduled on, to ensure that gas will not be leaked into the conduction oil around test specimen in displacement process, differential manometer adds with servo
Carry and be set to servo closed control.
Measuring pump ensures consistent with interlayer pressure P1 to the pressure P2 around test specimen, and shows the change of confined pressure flow in real time
Change, differential manometer DP1 setting value is 0, with Metering Pump Stroke servo closed control.Measuring pump rotates ISCO-100DM, and highest is resistance to
Pressure can reach 10000Psi (68.966MPa).
Measure control section
Measurement and Control System is passed by digital multichannel closed loop controller one, hydrostatic sensor, load sensor, displacement
Sensor and deformation-sensor composition;
(1) digital multichannel closed loop controller
Using advanced adaptive fuzzy pid control algorithm, the online precision of controlled quentity controlled variable of feasible system parameter
Closed-loop control, realizes the function such as constant speed plus off-load, constant force, permanent displacement.Simultaneously there is provided the control interface of custom system parameter, use
Family can be configured to system control parameters to adapt to different control environment, had with considerable flexibility.
Control system has 2 independent electrohydraulic servo valve control passages, various speed controls and control in process of the test
Function can switch mutually, and each actuator can closed-loop control servo valve works at the same time or separately according to test requirements document, it is ensured that
The either synchronously or asynchronously control of whole loading system, greatly improves the stability of pilot system.
Data collecting system has 9 tunnels, 24 A/D switching to pressure of high accuracy, displacement, deformation acquisition channel, can reach and show
It is worth accuracy:Within ± 0.1%.The sample rate of data has reached 10KHz, can rapidly gather current sensor letter
Number, so that closed loop control module preferably carries out real-time closed-loop control.
Digital multichannel closed loop measurement and control instrument can carry out instrument upgrading according to user's requirement.When event occurs in instrument
During barrier, maintenance process can be timely and conveniently carried out.
(2) sensor:
Sensor influences larger to testing machine precision, by putting into practice for many years, and displacement uses mangneto formula displacement transducer, and it is special
Putting is:High accuracy, high stability, high reliability, antijamming capability are extremely strong, low in energy consumption, are that sensor is most preferably tested in current displacement.
Axial pressure-bearing uses radial load sensor, and confined pressure is surveyed using hydrostatic sensor.
Described above is the preferred embodiment of the present invention, it is noted that for those skilled in the art
For, on the premise of principle of the present invention is not departed from, some improvements and modifications can also be made, these improvements and modifications
It should be regarded as protection scope of the present invention.