CN105352884B - Test the experimental method and component of concrete and coal, rock or concrete adhesion strength - Google Patents
Test the experimental method and component of concrete and coal, rock or concrete adhesion strength Download PDFInfo
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- CN105352884B CN105352884B CN201510260792.0A CN201510260792A CN105352884B CN 105352884 B CN105352884 B CN 105352884B CN 201510260792 A CN201510260792 A CN 201510260792A CN 105352884 B CN105352884 B CN 105352884B
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Abstract
The present invention relates to mechanical performance of concrete to test field, discloses a kind of experimental method for testing concrete and coal, rock or concrete adhesion strength, including step：Scene drills through by bonding testing piece, the making of bonding testing piece and maintenance, anchoring test specimen, installs test specimen, to drawing, reading, calculating adhesion strength；The invention also discloses a kind of experimental member for being used to test concrete and coal, rock or concrete adhesion strength, it includes two cohesive cylinders and two pull rods, one end of the bonding cylinder is equipped with threaded hole, one end of the pull rod is equipped with external screw thread, the pull rod is connected through a screw thread with the cohesive cylinder, and two cohesive cylinders are sheathed on the both ends of test specimen respectively.The present invention easy, quickly can directly measure concrete with spraying the adhesion strength of object.
Description
Technical field
The present invention relates to mechanical performance of concrete experimental technique field, more particularly to one kind test concrete and coal, rock
Or the experimental method and component of concrete adhesion strength.
Background technology
Bolt-spary supports is mine shaft, shaft station and main developing, the main technology of preparatory working permanent support.
Underworkings construction site, after concrete ejection to the roadway surrounding rock surface excavated condenses hardening, with country rock tight bond,
Cover and be integrated.In addition, the concrete of underground certain thickness (such as 200mm) is not an injection molding, but it is layered (every by several times
Secondary 50mm) injection forms, so after the concrete of spray on the contact surface of the two there is also certain with the concrete that first sprays
Bonding phenomenon；This concrete and spray object adhesion strength it is most important, adhesion strength it is too small or lose, concrete easily with
Country rock is peeled off, cracking, can not play its occluded air, moisture and the effect for supporting country rock；Adhesion strength is excessive, causes material unrestrained
Take, support cost rises, and increases roadway support quantities, influences the duration.Therefore, concrete and coal body, rock mass are accurately tested
And the adhesion strength of concrete body, it is very necessary to Concrete Injection Rock Bolting Design In Openings.
At present, the bond strength testing method that home and abroad colliery generally uses is Split-tension of Rolled method and drill core hubbing.This
Two methods respectively have advantage and disadvantage, but have a common issue to be that adhesion strength is obtained indirectly by result of the test, this is not
It can cause the inaccuracy and discreteness of test data with can avoiding.Also, the experimental rig of both approaches is complicated, sample dimensions
Huge, time consumption of experimental process is laborious, and particularly the latter will use motor in sampling process.It is well known that underground geological environment
Complexity, gas bearing, testing equipment explosion proof ratings are required it is high, especially for high methane or coal and gas outburst mine,
The pull-out test being powered in tunnel can cause downhole safety potential danger.In consideration of it, in order to it is more direct, easier,
More safely study gunite concrete and the adhesive property of coal and rock, it is necessary to above two method is improved, to experiment
Component is redesigned.
The content of the invention
(1) technical problems to be solved
The technical problem to be solved in the present invention is the bonding for how quickly and easily directly measuring concrete with spraying object
Intensity.
(2) technical solution
In order to solve the above technical problem, the present invention provides a kind of reality for testing concrete and coal, rock or concrete adhesion strength
Proved recipe method, it includes the following steps：
S1, scene are drilled through by bonding testing piece：Cylinder coal is drilled through respectively in underground coal mine, cylinder rock and is being sprayed
The position of upper concrete drills through cylinder concrete, as by bonding testing piece；
The making and maintenance of S2, bonding testing piece：Using cylinder die trial, first it is put into S1 and obtains in cylinder die trial bottom
By bonding testing piece, the good fresh concrete of the advance mixing in laboratory is then filled up in the cylinder die trial, is placed on vibration
Vibration compacting on platform, draws a marking line after concrete initial set in the two abutting edge, to show adhesive surface, is finally placed on mark and supports indoor support
Shield, is finally made bonding testing piece；
S3, anchoring test specimen：Appropriate binding agent first is added in two cohesive cylinders respectively, then tries obtained bonding in S2
One end of part is put into one of bonding cylinder, and the other end of the bonding testing piece is put into another and bonds in cylinder, it is ensured that bonds
The axis of test specimen and the axis of bonding cylinder point-blank, after to be bonded dose of solidification, fill respectively in one end of two cohesive cylinders
Upper connecting rod；
S4, installation test specimen：It is installed on test specimen is anchored made from S3 on mechanics machine, the upper beam folder of mechanics machine
Head clamps one end pull rod of anchoring test specimen, and bottom end rail collet clamps the other end pull rod of anchoring test specimen, ensures anchoring examination during installation
Part is vertical；
S5, to draw：Mechanics machine is started, moves down bottom end rail, and keeps test specimen by continuous uniform to drawing, at the same time
Pressure gauge reading change is observed, until test specimen is pulled off；
S6, reading：When test specimen is pulled off, pressure gauge reading no longer changes, and stops force at this time, finally records tensioning lotus
Carry；
S7, calculate adhesion strength：According to formulaCalculate the viscous of concrete and rock mass, coal body or concrete body
Knotting strength；In formula,
fb--- the adhesion strength of concrete and rock mass, coal body or concrete body, MPa；
F --- load of tensioning when test specimen is pulled off, KN；
The area of fracture of A --- test specimen, m2；
The plane of disruption of α --- test specimen and the angle of test specimen cross section, take 0 °.
Wherein, in step S3, binding agent uses polyurethane adhesive, and adhesion strength is not less than 5MPa, and setting time does not surpass
Cross 30s.
The present invention also provides a kind of experimental member for testing concrete and coal, rock or concrete adhesion strength, it includes two and glues
Tie cylinder and two pull rods, one end of the bonding cylinder is equipped with threaded hole, and one end of the pull rod is equipped with external screw thread, the pull rod and
The bonding cylinder is connected through a screw thread, and two cohesive cylinders are sheathed on the both ends of test specimen respectively.
Wherein, the cohesive cylinder is set with equipped with the opposite one end of threaded hole to be open.
Wherein, threaded hole size on two cohesive cylinders is identical, position is opposite.
Wherein, the cohesive cylinder and pull rod are made of cast steel.
(3) beneficial effect
Compared with prior art, the present invention has the following advantages：
A kind of experimental method for testing concrete and coal, rock or concrete adhesion strength provided by the invention, experiment essence is axis
Daraf(reciprocal of farad), by the cohesive body to drawing concrete and coal, rock, concrete block, immediately arrives at the adhesion strength of the two, experimental data it is accurate
Property more traditional Split-tension of Rolled method and drill core hubbing it is high, experimentation is time saving and energy saving, and experimental result is accurately easy to get；
A kind of experimental member for testing concrete and coal, rock or concrete adhesion strength provided by the invention, two cohesives cylinders with
Pull rod is process by common steel cylinder and rod iron, the two generally existing in actual life, convenient material drawing, and cost is low
It is honest and clean, and the processing technology of steel cylinder and rod iron is simple, easily shaping；
Cylinder and pull rod are bonded by threaded mechanical connection, it is simple in structure, it is easy to use, without electricity consumption, avoid in colliery
Spark is produced during down-hole application and causes security risk.
Brief description of the drawings
Fig. 1 is the integral installation structure diagram of experimental member of the present invention；
Fig. 2 is the bonding cylinder of experimental member of the present invention and the connection relationship diagram of pull rod.
In figure：1：Concrete；2：By bonding testing piece；3：Bond cylinder；4：Pull rod；5：Binding agent；6：Adhesive surface.
Embodiment
With reference to the accompanying drawings and examples, the embodiment of the present invention is described in further detail.Following instance
For illustrating the present invention, but it is not limited to the scope of the present invention.
In the description of the present invention, it is necessary to explanation, term " " center ", " longitudinal direction ", " transverse direction ", " on ", " under ",
The orientation or position relationship of the instruction such as "front", "rear", "left", "right", " vertical ", " level ", " top ", " bottom " " interior ", " outer " are
Based on orientation shown in the drawings or position relationship, it is for only for ease of the description present invention and simplifies description, rather than instruction or dark
Show that the component of meaning or element there must be specific orientation, with specific azimuth configuration and operation, thus it is it is not intended that right
The limitation of the present invention.
In the description of the present invention, it is necessary to illustrate, unless otherwise clearly defined and limited, term " installation ", " phase
Even ", " connection " should be interpreted broadly, for example, it may be being fixedly connected or being detachably connected, or be integrally connected；Can
To be mechanical connection or be electrically connected；It can be directly connected, can also be indirectly connected by intermediary, Ke Yishi
Connection inside two elements.For the ordinary skill in the art, with concrete condition above-mentioned term can be understood at this
Concrete meaning in invention.
The present invention provides a kind of experimental method for testing concrete and coal, rock or concrete adhesion strength, it includes step as follows
Suddenly：
S1, scene are drilled through by bonding testing piece 2：Typical tunnel is chosen in underground coal mine, is just disclosing the position difference of country rock
Drill through cylinder coal, cylinder rock by bonding testing piece 2, and cylinder concrete (coagulation is drilled through in the position for spraying concrete 1
Soil) by bonding testing piece 2, it is preferable that by 2 a diameter of 50mm of bonding testing piece, length is not less than 100mm；To simulate field condition,
Test coal, rock and concrete test specimen are drilled using the most common material of current down-hole application and formed；
The making and maintenance of S2, bonding testing piece：Using cylinder die trial, first it is put into S1 and obtains in cylinder die trial bottom
By bonding testing piece 2, the fresh concrete 1 of laboratory mixing is then filled up in the cylinder die trial, is put on a vibration table
Vibration compacting, a marking line is drawn after 1 initial set of concrete in the two abutting edge, to show adhesive surface 6, is finally placed on mark and is supported indoor support
Shield, is finally made bonding testing piece；
S3, anchoring test specimen：Appropriate binding agent 5 is first added in two cohesive cylinders 3 respectively, then by obtained bonding in S2
One end of test specimen is put into one of bonding cylinder 3, and the other end of the bonding testing piece is put into another and bonds in cylinder 3, it is ensured that
The axis of bonding testing piece and the axis of bonding cylinder 3 point-blank, after to be bonded dose 5 solidification, are loaded onto in the one end for bonding cylinder 3
Pull rod 4；
S4, installation test specimen：It is installed on test specimen is anchored made from S3 on mechanics machine, tensioning equipment uses WE-300B
Type fluid pressure type mechanics machine, realizes the tensioning to test specimen, by power by moving up and down between upper beam and moving beam
The upper beam collet for learning testing machine clamps one end pull rod 4 of anchoring test specimen, and the other end that bottom end rail collet clamps anchoring test specimen is drawn
Bar 4, ensures that anchoring test specimen is vertical during installation, avoids bias, the action direction that direction shown in arrow is pulling force F in Fig. 1；
S5, to draw：Mechanics machine is started, moves down bottom end rail, speed control is protected in 0.5~1.0MPa/s
Test specimen is held by continuous uniform to drawing, while observes pressure gauge reading change, until test specimen is pulled off；
S6, reading：When test specimen is pulled off, pressure gauge reading no longer changes, and stops force at this time, finally records tensioning lotus
Carry；
S7, calculate adhesion strength：According to formulaCalculate the viscous of concrete 1 and rock mass, coal body or concrete body
Knotting strength；In formula,
fb--- the adhesion strength of concrete 1 and rock mass, coal body or concrete body, MPa；
F --- load of tensioning when test specimen is pulled off, KN；
The area of fracture of A --- test specimen, m2；
The plane of disruption of α --- test specimen and the angle of test specimen cross section, take 0 °.
Wherein, in step S3, binding agent 5 uses polyurethane adhesive, and adhesion strength is not less than 5MPa, and setting time does not surpass
Cross 30s.
The one kind tested using the test concrete 1 of the present invention and the experimental method of coal, rock or concrete adhesion strength is real
The result of calculation for applying example is shown in Table 1：
The bonding strength test result of 1 concrete 1 of table and rock, coal and concrete 1
Once experiment finishes.By the cohesive body to drawing concrete 1 and coal, rock, concrete block, the bonding for immediately arriving at the two is strong
Degree, the more traditional Split-tension of Rolled method of the accuracy of experimental data and drill core hubbing are high, and experimentation is time saving and energy saving, experimental result
Accurately it is easy to get.
As depicted in figs. 1 and 2, present invention also offers a kind of experiment for testing concrete 1 and coal, rock or concrete adhesion strength
Component, it includes two cohesive cylinders 3 and two pull rods 4, and one end of the bonding cylinder 3 is equipped with threaded hole, one end of the pull rod 4
Equipped with external screw thread, the pull rod 4 is connected through a screw thread with the cohesive cylinder 3, and two cohesive cylinders 3 are sheathed on tested respectively
The both ends of part, bond cylinder 3, with mechanics machine to drawing both ends pull rod 4, gained stretching force with being connected with externally threaded pull rod 4
The as adhesion strength of the two.
For the ease of installation, the bonding cylinder 3 is set with equipped with the opposite one end of threaded hole to be open.
In order to ensure to neutrality, it is ensured that test specimen axis and bond cylinder 3 axis point-blank, two cohesive cylinders 3
On threaded hole size is identical, position is opposite.
Wherein, the cohesive cylinder 3 and pull rod 4 are formed from steel.Preferably, it is steel hollow cylinder to bond cylinder 3, internal diameter
50mm, outside diameter 65mm, wall thickness 15mm, axial length 80mm, top is open, and bottom is provided with the screwed hole of centre of an a diameter of 25mm
(being used for connecting rod 4).Pull rod 4 is preferably diameter 25mm, the steel cylinder of long 120mm.
Two cohesive cylinders 3 and pull rod 4 are process by common steel cylinder and rod iron, the two is general in actual life
Store-through exists, convenient material drawing, of low cost, and the processing technology of steel cylinder and rod iron is simple, easily shaping；Bond cylinder 3 and pull rod 4
It is simple in structure by threaded mechanical connection, it is easy to use, without electricity consumption, avoid and spark is produced when underground coal mine is applied, and
Cause security risk.
As can be seen from the above embodiments, the present invention quickly and easily can directly measure concrete 1 with spraying object
Adhesion strength, test are accurate.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all essences in the present invention
With within principle, any modification, equivalent replacement, improvement and so on, should all be included in the protection scope of the present invention god.
Claims (2)
1. a kind of experimental method for testing concrete and coal, rock or concrete adhesion strength, it is characterised in that include the following steps：
S1, scene are drilled through by bonding testing piece：Cylinder coal, cylinder rock and mixed having sprayed are drilled through respectively in underground coal mine
The position for coagulating soil drills through cylinder concrete, as experiment by bonding testing piece；
The making and maintenance of S2, bonding testing piece：Using cylinder die trial, the quilt obtained in S1 is first put into cylinder die trial bottom
Bonding testing piece, then fills up the prefabricated fresh concrete in laboratory in the cylinder die trial, put vibrate on a vibration table it is close
It is real, a marking line is drawn in the two abutting edge after concrete initial set, to show adhesive surface, mark is finally placed on and supports indoor maintenance, final system
Into bonding testing piece；
S3, anchoring test specimen：Appropriate binding agent first is added in two cohesive cylinders respectively, then by obtained bonding testing piece in S2
One end is put into one of bonding cylinder, and the other end of the bonding testing piece is put into another and bonds in cylinder, it is ensured that bonding testing piece
Axis and bond cylinder axis point-blank, to be bonded dose solidification after, load onto drawing respectively in one end of two cohesive cylinders
Bar；
S4, installation test specimen：It is installed on test specimen is anchored made from S3 on mechanics machine, by the upper beam collet of mechanics machine
One end pull rod of anchoring test specimen is clamped, bottom end rail collet clamps the other end pull rod of anchoring test specimen, ensures anchoring test specimen during installation
Vertically；
S5, to draw：Mechanics machine is started, moves down bottom end rail, and keeps test specimen, to drawing, to be observed at the same time by continuous uniform
Pressure gauge reading changes, until test specimen is pulled off；
S6, reading：When test specimen is pulled off, pressure gauge reading no longer changes, and stops force at this time, finally records tensile load；
S7, calculate adhesion strength：According to formulaThe bonding for calculating concrete and rock mass, coal body or concrete body is strong
Degree；In formula,
fb--- the adhesion strength of concrete and rock mass, coal body or concrete body, MPa；
F --- load of tensioning when test specimen is pulled off, KN；
The area of fracture of A --- test specimen, m2；
The plane of disruption of α --- test specimen and the angle of test specimen cross section, take 0 °.
2. the experimental method of test concrete and coal, rock or concrete adhesion strength as claimed in claim 1, it is characterised in that step
In rapid S3, binding agent uses polyurethane adhesive, and adhesion strength is not less than 5MPa, and setting time is no more than 30s.
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| CN105352884B true CN105352884B (en) | 2018-05-15 |
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Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105784589A (en) * | 2016-03-10 | 2016-07-20 | 中国矿业大学 | Method for testing binding force of anchoring agent and rock interface |
| FR3054038A1 (en) * | 2016-07-13 | 2018-01-19 | Aia Ingenierie | METHOD FOR DETERMINING PARAMETERS DEFINING COHESIVE LAWS REPRESENTING THE BEHAVIOR OF A MORTAR JOINT BETWEEN TWO STONES |
| CN107727569B (en) * | 2017-09-30 | 2019-02-22 | 华北水利水电大学 | A kind of test method for testing rock and concrete binding interface tensile strength |
| CN107677596B (en) * | 2017-09-30 | 2018-12-28 | 华北水利水电大学 | The method of indoor test rock and concrete binding interface tensile strength |
| CN110108529A (en) * | 2019-05-13 | 2019-08-09 | 河海大学 | A kind of rocks-concrete assembly preparation method of sample |
| CN110196225B (en) * | 2019-06-25 | 2022-03-01 | 河南理工大学 | Device and method for testing bonding strength of rock and sprayed concrete contact surface |
| CN110514585A (en) * | 2019-09-10 | 2019-11-29 | 中国水利水电第五工程局有限公司 | A kind of gunite concrete and country rock adhesion strength measurement device |
| CN111766200B (en) * | 2020-06-29 | 2022-08-09 | 中国人民解放军陆军工程大学 | Test device and method for measuring dynamic bonding strength of sprayed concrete under blasting disturbance |
| CN111896546A (en) * | 2020-07-02 | 2020-11-06 | 上海市建筑科学研究院有限公司 | New and old concrete joint surface quality detection method based on drilling and core drilling sampling |
| CN112878986B (en) * | 2021-01-22 | 2022-03-25 | 西南石油大学 | Device and method for testing mechanical property and sealing property of cement sheath-formation interface of oil and gas well |
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| CN2324542Y (en) * | 1997-10-20 | 1999-06-16 | 中国科学院武汉岩土力学研究所 | Combined sleeve type rock specimen pressing-pulling converter |
| CN202583048U (en) * | 2012-05-07 | 2012-12-05 | 长安大学 | Device for detecting bonding strength of interface between road asphalt and aggregate |
| CN104122203A (en) * | 2014-08-12 | 2014-10-29 | 中国铁道科学研究院铁道建筑研究所 | Testing method of tensile adhesive strength of flexible polyurethane foam material for polyurethane solidification track bed |
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| US7415890B2 (en) * | 2003-11-13 | 2008-08-26 | Deslauriers, Inc. | Unbonded system for strength testing of concrete masonry units |
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| CN2324542Y (en) * | 1997-10-20 | 1999-06-16 | 中国科学院武汉岩土力学研究所 | Combined sleeve type rock specimen pressing-pulling converter |
| CN202583048U (en) * | 2012-05-07 | 2012-12-05 | 长安大学 | Device for detecting bonding strength of interface between road asphalt and aggregate |
| CN104122203A (en) * | 2014-08-12 | 2014-10-29 | 中国铁道科学研究院铁道建筑研究所 | Testing method of tensile adhesive strength of flexible polyurethane foam material for polyurethane solidification track bed |
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