CN115931551A - Method for measuring shearing mechanical parameters of anchoring interface by utilizing indoor drawing test - Google Patents
Method for measuring shearing mechanical parameters of anchoring interface by utilizing indoor drawing test Download PDFInfo
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Abstract
The invention provides a method for measuring shearing mechanical parameters of an anchoring interface by utilizing an indoor drawing test, and relates to the technical field of mechanical test tests. The method comprises the following steps: measuring axial rigidity and strength of an anchoring interface by using a short anchor rod drawing test, and determining interface rigidity and strength parameters of the anchor rod in a drawing elastic stage; carrying out anchor rod drawing loading by using a testing machine, monitoring the total amount of the tensile deformation and the drawn relative displacement of the anchor rod in the drawing process, and obtaining a relation curve of the anchor rod drawing load and the relative displacement; calculating the relative displacement between the anchor rod and the anchoring base; determining a relation curve of the shear stress and the displacement of the anchoring interface; and calculating the axial shear strength and the axial shear rigidity of the anchoring interface. The method can determine the rigidity and the shear strength of an anchoring interface and the damage evolution law thereof under the conditions of different anchor rods, different lithologies, different anchoring agents and the like.
Description
Technical Field
The invention relates to the technical field of mechanical test tests, in particular to a method for measuring shearing mechanical parameters of an anchoring interface by utilizing an indoor drawing test.
Background
The bearing effect of the anchor rod anchoring system is that the anchor rod is drilled and embedded in the surrounding rock, the anchor rod and the surrounding rock are effectively contacted by adopting a mechanical mode or a bonding material, the anchor rod transmits an external load or balances an internal load through a contact interface so as to fully transfer the self bearing capacity of the surrounding rock, and thus, a reinforced anchoring system of the anchor rod-surrounding rock cooperative work is formed. Therefore, the contact mechanical property of the anchoring interface is the key to determine the load-bearing performance of the anchor rod anchoring system.
The actual interface physical structure and the mechanical action of the anchoring of the deformed steel anchor rod are complex, the actual interface physical structure and the mechanical action comprise an adhesion and mechanical occlusion interface of the anchor rod and an anchoring agent and an adhesion interface of the anchoring agent and surrounding rock, the adhesion is mainly used, and if the surrounding rock is drilled with rough holes, the mechanical occlusion action is obvious. The simulation analysis aiming at the physical structure of the real interface is difficult, and the simulation parameters are not easy to be calibrated through tests. The interface model is established by simplifying the original model and correctly representing the mechanical behavior of the original model, the simplest and most effective method is to simplify the real anchoring interface into a smooth interface, namely, simplify the anchor rods with various rib structures into smooth round anchor rods, simplify the uneven surrounding rock drilling into smooth drilling holes, simplify the anchoring agent layer with thickness into a contact surface without thickness, and then obtain the interface mechanical parameters, particularly the interface rigidity, the shear strength and the like in the pulling direction of the anchor rods on the basis of test calibration and theoretical analysis so as to effectively simulate the indoor test and engineering test results.
The failure of the anchoring interface of the anchor rod is mainly the shear failure of the interface of the anchor rod and the anchoring agent or the anchoring agent and the surrounding rock, and the maximum shear stress which can be provided by the interface is the shear strength. The interface rigidity refers to the capability of a contact interface to resist the displacement of the interface under the action of interface stress, namely the capability of resisting deformation or sliding. In the aspect of finite element calculation, the interface convergence difficulty and the overall structure rigidity are caused by excessively large interface rigidity value, and the overall structure rigidity is caused by excessively small rigidity value. The interface rigidity performance has important influence on load transmission and damage of the interface, and is a key factor for controlling the integral rigidity and performance of the structure, and the interface rigidity is also an important parameter for theoretical analysis and numerical calculation.
Disclosure of Invention
In order to clarify the axial shear stiffness and strength parameters of the anchoring interface and effectively analyze and simulate the results of indoor tests and engineering tests, the invention provides a method for measuring the shear mechanical parameters of the anchoring interface by utilizing an indoor pull test, and the specific technical scheme is as follows.
A method for determining shear mechanics parameters of an anchoring interface using an indoor pull test, the method comprising:
s1, calculating axial rigidity and strength of an anchoring interface measured by a short anchor rod drawing test through a numerical simulation method, and determining interface rigidity and strength parameters of an anchor rod drawing elastic stage;
s2, carrying out an anchor rod drawing loading test by using a testing machine, monitoring the tensile deformation and the relative displacement of the pulled anchor rod in the drawing process, and obtaining a relation curve of the anchor rod drawing load and the relative displacement;
s3, calculating the relative displacement between the anchor rod and the anchoring base body;
s4, calculating and determining a relation curve of the average shear stress and the displacement of the anchoring interface;
s5, calculating the axial shear strength of the anchoring interface, and calculating the axial shear stiffness of the anchoring interface;
and S6, determining the evolution parameters of the rigidity damage of the anchoring interface.
Preferably, the step of the bolt pull loading test comprises:
installing an anchoring and drawing device on a material tensile testing machine, placing an anchoring base body of an anchor rod drawing sample in the anchoring and drawing device, clamping a test anchor rod by the testing machine, installing a U-shaped fixing piece at the free end of the test anchor rod, installing an L-shaped fixing piece at the port position of the anchoring base body, respectively connecting the two ends of an extensometer with the U-shaped fixing piece and the L-shaped fixing piece, and enabling the distance between the U-shaped fixing piece and the L-shaped fixing piece to be equal to the gauge length of the extensometer; and applying a drawing force to the anchor rod by using the material tensile testing machine to obtain a relation curve of the relative displacement between the drawing load of the anchor rod and the fixed point of the extensometer on the anchor rod.
Preferably, the relative displacement delta of the bolt pull cross-section is s1 The calculation method of (A) is as follows:
wherein, delta s0 The displacement of the drawing end of the anchor rod is obtained; l e The scale distance of the extensometer is adopted; d is a radical of b Is the diameter of the anchor rod; e b Is the modulus of elasticity of the anchor material.
Preferably, the anchoring interface has an average shear stress τ s1 The calculation method is as follows:
wherein, P 1 Drawing load for the short anchor rod; d b Is the anchoring interface diameter; l. the a The anchoring length for pulling the short anchor rod.
Preferably, the axial shear strength [ tau ] of the anchoring interface s ]The calculation method of (A) is as follows:
wherein, P 1max Drawing limit load for the short anchor rod; d b Is the anchoring interface diameter; l a The anchoring length for pulling the short anchor rod.
Preference is given toCalculating the slope k at the elastic stage point according to the relation curve of the average shear stress and the displacement of the anchoring interface ss1 The calculation method is as follows:
wherein, Δ τ s1 The axial shear stress variation of the anchoring interface is obtained; delta delta s1 For the variation of the relative displacement of the anchoring interface, [ tau ] s ]The shear strength corresponding to the drawing limit load;
and (4) shear displacement corresponding to the drawing limit load.
Preferably, the anchor interface stiffness damage evolution parameters include post-peak shear strength, post-peak shear stiffness damage parameters.
Preferably, the post-peak shear strength [ tau' s ]The calculation method is as follows:
[τ s ]＝[τ s ](1-D τ )
wherein D is τ For the shear strength damage variable, [ tau ] s ]The shear strength of the anchoring interface;
the post peak shear stiffness k' ss1 The calculation method is as follows:
k′ ss1 ＝k ss1 (1-D k )
wherein D is k For axial shear stiffness impairment variables, k ss1 The slope at the point of the elastic phase.
Preferably, the axial shear stiffness damage variable D k The calculation method is as follows:
wherein, delta s Relative displacement of the anchoring interface after the peak;
drawing limit loadShearing and displacing; d τ Is the shear strength damage variable.
The method for determining the shearing mechanical parameters of the anchoring interface by utilizing the indoor drawing test has the beneficial effects that:
(1) The short anchor rod drawing test is utilized to measure and calibrate the mechanical parameters of the anchoring interface, the drawing anchoring length of the short anchor rod is small, the axial force difference value of the anchor rod in the anchoring length range is small, the deformation of the anchor rod along the anchoring length can be ignored, and the interface shear stress is assumed to be uniformly distributed.
(2) Considering that the simulation of a real interface physical structure is difficult, simulation parameters are not easy to calibrate through tests, the method simplifies a real anchoring interface into a smooth interface, simplifies an anchoring agent layer with thickness into a contact surface without thickness, and obtains the axial interface rigidity, the shear strength and the interface axial rigidity damage variable of the anchor rod so as to realize effective simulation and simulate and determine a test result.
(3) When the anchor rod drawing and loading test is carried out in the method, the displacement of the end of the anchor rod is measured in a mode that extensometers are fixed on the anchoring base body and the surface of the anchor rod, the method is simple and practical, the measurement precision is high, the calculation method of the relative displacement of the anchoring interface is provided according to the measurement result, and the relation curve of the shearing stress and the shearing displacement of the anchoring interface can be effectively obtained.
(4) By analyzing the drawing test result of the short anchor rod, a calculation method for obtaining the axial shear strength, the axial rigidity and the damage evolution parameters of the interface is provided, and a method flow for accurately measuring the relative displacement of the anchoring interface and calibrating the axial mechanical parameters of the anchoring interface in an indoor test is provided.
Drawings
FIG. 1 is a schematic diagram of a drawing anchoring interface analysis of a deformed steel bar anchor rod;
FIG. 2 is a schematic diagram of a drawing anchoring interface analysis of a round steel anchor rod;
FIG. 3 is a schematic view of the anchoring pull-out device;
FIG. 4 is a schematic diagram of relative displacement measurement of an anchoring interface of a short anchor rod pull test piece;
FIG. 5 is a schematic view of the axial shear strength and stiffness analysis of a short bolt pull anchor interface;
FIG. 6 is a schematic view of the axial shear strength and stiffness analysis of a long bolt pull-out anchoring interface;
FIG. 7 is a flow chart of short bolt pull-out anchoring interface axial shear strength and stiffness analysis;
FIG. 8 is a graph of short bolt pull test data;
FIG. 9 is a graph of short bolt pull test smoothing data;
FIG. 10 is an anchoring interface axial shear stiffness damage variable versus displacement;
FIG. 11 shows the results of the test of the pull load-displacement curve of the anchor rods with different anchoring lengths;
fig. 12 shows the result of numerical simulation of the pull load-displacement curve of the anchor rod with different anchoring lengths.
In the figure: 1-rock; 2-an anchoring agent; 3, anchoring the rod; 4-element node; 5-U-shaped fixing piece; 6-L-shaped fixing pieces; 7-a connector; 8-a bolt; 9-anchoring and pulling device; 10-a testing machine; 100-extensometer.
Detailed Description
An embodiment of the method for measuring the shear mechanical parameters of the anchoring interface by using the indoor drawing test provided by the invention is described with reference to fig. 1 to 12.
A method for determining shearing mechanical parameters of an anchoring interface by utilizing an indoor drawing test starts from analysis of a relative displacement angle between a node position on one side of an anchor rod and a node on one side of an anchoring base body, firstly, interface rigidity and strength parameters of the pulling elasticity stage of the anchor rod are determined, and then, a change rule and a corresponding relation of an anchoring interface strength damage variable and a rigidity damage variable along with displacement are further calibrated.
The method comprises the following specific steps:
s1, calculating axial rigidity and strength of an anchoring interface measured by a short anchor rod drawing test through a numerical simulation method, and determining interface rigidity and strength parameters of the anchor rod in a drawing elastic stage.
Specifically, the anchor rod mainly bears the shearing action in the drawing direction during drawing, the shearing action is described to have two important parameters, namely shear strength and shear rigidity, and after the two parameters are determined, indoor test and engineering test results can be simulated by using a numerical calculation means. As shown in fig. 1, the current engineering anchor rod is usually a deformed steel anchor rod, and due to the existence of the surface rib of the anchor rod, the actual interface physical structure of the anchor rod anchoring is complex, and numerical simulation is not easy to perform. Therefore, a proper interface mechanical model can be adopted, the complex anchoring interface is simplified into a smooth anchoring interface shown in fig. 2, the complex anchoring interface mechanical model parameters are obtained by using a method for measuring the axial rigidity and the strength of the anchoring interface through a short anchor rod pull test, and the specific implementation method flow is shown in fig. 7.
S2, carrying out an anchor rod drawing loading test by using a testing machine, monitoring the tensile deformation and the drawn-out relative displacement of the anchor rod in the drawing process, and obtaining a relation curve of the anchor rod drawing load and the relative displacement.
Wherein, the step that the stock was drawn the loading test includes: installing an anchoring drawing device on a material tensile testing machine, placing an anchoring base body of an anchor rod drawing sample in the anchoring drawing device, wherein the anchoring drawing device is a rectangular frame with a lower opening, and the upper part of the anchoring drawing device is connected with the testing machine through a bolt; the testing machine lower part centre gripping test stock, the free end installation U-shaped mounting of test stock, anchor base member port position installation L shape mounting, the extensometer both ends are connected with U-shaped mounting and L shape mounting respectively, and the interval between U-shaped mounting and the L shape mounting equals the gauge length of extensometer, and the extensometer monitors the relative displacement between two mountings. The material tensile testing machine applies drawing force to the anchor rod to obtain a relation curve of the relative displacement between the drawing load of the anchor rod and the fixed point of the extensometer on the anchor rod, namely P 1 -δ s0 Curve line.
The most important thing of the short anchor rod drawing test is to realize the accurate measurement of the relative displacement of the anchor rod and the anchoring base body, and the deformation of the anchoring agent is included in the anchoring interface mechanical analysis model during the measurement, namely the anchoring construction factor is considered during the calibration of the interface mechanical model.
And S3, calculating the relative displacement between the anchor rod and the anchoring base body.
Relative displacement delta s0 Including the relative displacement between the anchor rod and the anchoring base body andthe deformation of the free section of the anchor rod in the range of the scale distance of the extensometer needs to be separated, only the relative displacement between the anchor rod and the anchoring substrate is obtained, and the relative displacement delta of the drawing section of the anchor rod s1 The calculation method is as follows:
wherein, delta s0 The displacement of the drawing end of the anchor rod is obtained; l e The gauge length of the extensometer (namely the distance from the extensometer fixing point on the anchor rod to the anchoring base); d is a radical of b Is the diameter of the anchor rod; e b Is the modulus of elasticity of the anchor material.
And S4, calculating and determining a relation curve of the average shear stress and the displacement of the anchoring interface.
Mean shear stress tau of anchoring interface s1 The calculation method of (A) is as follows:
wherein, P 1 Drawing load for the short anchor rod; d b Is the anchoring interface diameter (equivalent diameter of the anchor rod); l a The anchoring length for pulling the short anchor rod.
And S5, calculating the axial shear strength of the anchoring interface and calculating the axial shear stiffness of the anchoring interface.
According to the relation curve of shear stress and displacement of the anchoring interface, the final point of the elastic stage is the maximum shear strength, and according to the assumption of the average distribution of the pull-out shear stress of the short anchor rod, the axial shear strength [ tau ] of the anchoring interface can be obtained according to the maximum pull-out load s ]The calculation method is as follows:
wherein, P 1max Drawing limit load for the short anchor rod; d b Is the anchor interface diameter (equivalent diameter of the anchor rod); l a The anchoring length for pulling the short anchor rod.
According to the relation curve of the average shear stress and the displacement of the anchoring interface, a point is taken at the elastic stage to calculate the slope, namely the axial shear stiffness of the interface, and the slope k at the elastic stage point is calculated ss1 The calculation method is as follows:
wherein, Δ z τ s1 The axial shear stress variation of the anchoring interface is obtained; delta delta s1 For the variation of the relative displacement of the anchoring interface, [ tau ] s ]The shear strength corresponding to the drawing limit load; delta s Shear displacement corresponding to the drawing limit load.
And S6, determining the evolution parameters of the rigidity damage of the anchoring interface.
Wherein the anchor interface stiffness damage evolution parameters comprise post-peak shear strength, post-peak shear stiffness and post-peak shear stiffness damage parameters.
Post peak shear strength [ τ' s ]The calculation method of (A) is as follows:
[τ′ s ]＝[τ s ](1-D τ )
wherein D is τ For the shear strength damage variable, [ tau ] s ]The shear strength of the anchoring interface;
post peak shear stiffness k' ss1 The calculation method of (A) is as follows:
k′ ss1 ＝k ss1 (1-D k )
wherein D is k For axial shear stiffness impairment variables, k ss1 The slope at the point of the elastic phase.
Axial shear stiffness damage variable D k The calculation method is as follows:
wherein, delta s Relative displacement of the anchoring interface after the peak;
ultimate drawing load stationCorresponding shear displacement; d τ Is the shear strength damage variable.
The method is based on a short anchor rod drawing indoor test, and the relative displacement of an anchoring interface is accurately measured to obtain the parameters of the anchoring interface. For the measurement of the deformation of a certain point of an anchor rod sample, the most common method is an extensometer measurement method, when the length size of the anchor rod is small, the shearing stress of an anchoring interface along the length direction of the anchor rod can be assumed to be uniformly distributed, and the relative shearing displacement (anchor rod-anchoring matrix relative displacement) at different positions on the interface is also assumed to be consistent.
As shown in fig. 5, the following specific examples are provided:
wherein the anchoring length l of the short anchor rod is drawn a =50mm, anchor rod exposes section extensometer 100 and measures length l e =200mm; as shown in fig. 6, the length L of the anchoring section is drawn by the long anchor a =500mm, anchor rod exposes a section extensometer 100 and measures length L e =200mm; the anchoring length ratio n =10 of the long anchor rod and the short anchor rod. Diameter d of anchor rod b =20mm, modulus of elasticity E b ＝200GPa。
FIG. 8 shows a drawing load-interface displacement curve measured by a short anchor rod drawing test, and the shear stress-interface displacement curve of the anchoring interface shown in FIG. 9 is obtained according to the curve, and the axial shear strength [ tau ] of the anchoring interface is measured s ]Calculating the axial shear strength [ tau ] of the anchoring interface s ]=9.55MPa; according to the slope k at the elastic phase point ss1 Calculating the axial shear stiffness of the anchoring interface to be k ss1 =5.0MPa/mm; according to axial shear stiffness damage variable D k The variation curve of the damage variable of the axial shear stiffness of the anchoring interface along with the displacement of the interface is obtained by the calculation method of (3), as shown in fig. 10, and then the damage variable D is obtained k A list of values is shown in the following table.
| Damage variable D k | Shear displacement delta s / |
| 0 | 0 |
| 0.19 | 0.55 |
| 0.32 | 1.04 |
| 0.4 | 1.73 |
| 0.54 | 2.49 |
| 0.67 | 4.02 |
| 0.77 | 5.61 |
| 0.85 | 7.69 |
| 0.91 | 11.29 |
| 0.97 | 18.07 |
| 0.98 | 27.29 |
| 1 | 46.68 |
According to the method, a real anchoring interface is simplified into a smooth interface, an anchoring agent layer with thickness is simplified into a contact surface without thickness, and the axial interface rigidity, the shear strength and the interface axial rigidity damage variable of the anchor rod are obtained, so that effective simulation is realized, and a test result is simulated and determined. When the anchor rod drawing and loading test is carried out, the displacement of the end head of the anchor rod is measured in a mode of fixing extensometers on the surface of the anchor rod and the anchor base body, the method is simple and practical, the measurement precision is high, the calculation method of the relative displacement of the anchoring interface is provided according to the measurement result, and the relation curve of the shearing stress and the shearing displacement of the anchoring interface can be effectively obtained. By analyzing the drawing test result of the short anchor rod, a calculation method for obtaining the axial shear strength, the axial rigidity and the damage evolution parameters of the interface is provided, and a method flow for accurately measuring the relative displacement of the anchoring interface and calibrating the axial mechanical parameters of the anchoring interface in an indoor test is also provided. The method can effectively determine the rigidity and the shear strength of the anchoring interface and the damage evolution rule thereof under the conditions of different anchor rods, different lithologies, different anchoring agents and the like.
It is to be understood that the above description is not intended to limit the present invention, and the present invention is not limited to the above examples, and those skilled in the art may make modifications, alterations, additions or substitutions within the spirit and scope of the present invention.
Claims (9)
1. A method for determining shear mechanical parameters of an anchoring interface by utilizing an indoor drawing test is characterized by comprising the following steps:
s1, calculating axial rigidity and strength of a short anchor rod drawing test measuring anchoring interface by a numerical simulation method, and determining interface rigidity and strength parameters of an anchor rod drawing elastic stage;
s2, carrying out an anchor rod drawing loading test by using a testing machine, monitoring the tensile deformation and the relative displacement of the pulled anchor rod in the drawing process, and obtaining a relation curve of the anchor rod drawing load and the relative displacement;
s3, calculating the relative displacement between the anchor rod and the anchoring base body;
s4, calculating and determining a relation curve of the average shear stress and the displacement of the anchoring interface;
s5, calculating the axial shear strength of the anchoring interface, and calculating the axial shear stiffness of the anchoring interface;
and S6, determining the evolution parameters of the rigidity damage of the anchoring interface.
2. The method for determining the shear mechanical parameters of the anchoring interface through the indoor pull test as claimed in claim 1, wherein the step of the anchor rod pull loading test comprises:
installing an anchoring and pulling device on a material tensile testing machine, placing an anchoring base body of an anchor rod pulling sample in the anchoring and pulling device, clamping a test anchor rod by the testing machine, installing a U-shaped fixing piece at the free end of the test anchor rod, installing an L-shaped fixing piece at the port position of the anchoring base body, respectively connecting the two ends of an extensometer with the U-shaped fixing piece and the L-shaped fixing piece, and enabling the distance between the U-shaped fixing piece and the L-shaped fixing piece to be equal to the gauge length of the extensometer; and applying a drawing force to the anchor rod by the material tensile testing machine to obtain a relation curve of the drawing load of the anchor rod and the relative displacement between the drawing load of the anchor rod and the fixed point of the extensometer on the anchor rod.
3. The method for determining the shear mechanics parameter of an anchoring interface according to claim 1, wherein the relative displacement δ of the cross-section of the anchor rod in the drawing process is the same as the relative displacement δ of the cross-section of the anchor rod in the drawing process s1 The calculation method of (A) is as follows:
wherein, delta s0 The displacement of the drawing end of the anchor rod is obtained; l e The gauge length of the extensometer; d b Is the diameter of the anchor rod; e b Is the modulus of elasticity of the anchor material.
4. The method for determining the shear mechanical parameters of the anchoring interface by using the indoor drawing test as claimed in claim 1, wherein the average shear stress τ of the anchoring interface s1 The calculation method is as follows:
wherein, P 1 Drawing load for the short anchor rod; d b Is the anchoring interface diameter; l a The anchoring length for pulling the short anchor rod.
5. The method for determining the shear mechanics parameter of an anchoring interface according to claim 1, wherein the axial shear strength [ τ ] of the anchoring interface is determined by a laboratory pull test s ]The calculation method of (A) is as follows:
wherein, P 1max Drawing limit load for the short anchor rod; d b Is the anchoring interface diameter; l a The anchoring length for pulling the short anchor rod.
6. The method for determining the shear mechanics parameters of an anchoring interface according to claim 1, wherein the slope k at the elastic phase point is calculated according to the relation curve of the average shear stress and the displacement of the anchoring interface ss1 The calculation method of (A) is as follows:
wherein, Δ τ s1 The axial shear stress variation of the anchoring interface is adopted; delta delta s1 Is the relative displacement variation of the anchoring interface, [ tau ] s ]Shear strength corresponding to the drawing limit load;
shear displacement corresponding to the drawing limit load.
7. The method for determining shear mechanical parameters of an anchoring interface by using an indoor drawing test as claimed in claim 1 or 6, wherein the damage evolution parameters of the stiffness of the anchoring interface comprise post-peak shear strength, post-peak shear stiffness and post-peak shear stiffness damage parameters.
8. The method for determining shear mechanical parameters of anchoring interface by using indoor drawing test as claimed in claim 7, wherein the post-peak shear strength [ τ' s ]The calculation method is as follows:
[τ′ s ]＝[τ s ](1-D τ )
wherein D is τ As a variable of the shear strength damage, [ tau ] s ]The shear strength of the anchoring interface;
the post peak shear stiffness k' ss1 The calculation method is as follows:
k′ ss1 ＝k ss1 (1-D k )
wherein D is k For axial shear stiffness impairment variable, k ss1 The slope at the point of the elastic phase.
9. The method for determining shear mechanical parameters of an anchoring interface according to claim 8, wherein the axial shear stiffness damage variable D is k The calculation method is as follows:
wherein, delta s Relative displacement of the anchoring interface after the peak;
shearing displacement corresponding to the drawing limit load; d τ Is the shear strength damage variable. />
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116204968A (en) * | 2023-05-05 | 2023-06-02 | 中国矿业大学(北京) | Anchor rod and anchor agent and surrounding rock coupling effect anchor rod anchoring performance determining method |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116204968A (en) * | 2023-05-05 | 2023-06-02 | 中国矿业大学(北京) | Anchor rod and anchor agent and surrounding rock coupling effect anchor rod anchoring performance determining method |
| CN116204968B (en) * | 2023-05-05 | 2023-07-04 | 中国矿业大学(北京) | Anchor rod and anchor agent and surrounding rock coupling effect anchor rod anchoring performance determining method |
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