Abstract: A three-dimensional dynamic and static load test system for simulating deep roadway excavation and a method thereof are provided, which relates to the technical field of indoor simulation testing in underground engineering. The system includes a mobile platform, a box body, a support frame, a roadway excavation device, and a data monitoring unit. The system and method of the disclosure can reproduce the whole process of roadway excavation, simulate the multi-directional loading of deep roadway, and restore the real stress state of deep roadway under the influence of dynamic and static load superimposed disturbance. The problem of insufficient research under the condition of unidirectional static loading and lack of multi-directional dynamic and static loading in current large-scale experimental devices has been solved, and the stress and deformation of the surrounding rock of the roadway are reflected in real-time through the data monitoring unit.

Abstract: A device includes a pressure measuring segment, a connecting rod, a hydraulic pump, a pressure gauge, a high-pressure oil pipe, a pressure control valve, a tray, a push rod and a connection casing. The pressure measuring segment is on the connecting rod, a front end of the push rod is connected with the connecting rod, the tray is at a rear end of the push rod, the connection casing is connected with the tray. The pressure measuring segment includes a main pipe, a hydraulic bladder, a fixing ring, a barrier sheet, an outer pillow housing and a connection sleeve. Both ends of the hydraulic bladder are sleeved on the main pipe, an oil inlet is in communication with the hydraulic bladder, the outer pillow housing is sleeved on the main pipe, the connection sleeve is wrapped around the outer pillow housing.

Abstract: A cyclic dynamic loading-confining pressure instantaneous unloading test device includes a load-supporting frame system, a cyclic dynamic loading system, a confining pressure loading system, a monitoring system, a control system and a data analysis system; the top of the load-supporting frame system is equipped with the cyclic dynamic loading system, the cyclic dynamic loading system is connected with the control system, the bottom of the load-supporting frame system is equipped with the confining pressure loading system, the cyclic dynamic loading system and the confining pressure loading system are equipped with the monitoring system, the monitoring system and the control system are connected with the data analysis system.

Abstract: A collaborative erosion-control method of releasing-splitting-supporting based on coal mass pressure relief and roof pre-splitting provided by the disclosure includes the following steps: step 1, driving into a coal seam to release pressure; step 2, low roof pre-splitting during driving process; step 3, supporting of roadway surrounding rock and support reinforcement; step 4, floor destressing of the roadway; step 5, high roof pre-splitting before mining; step 6, destressing and supporting of the advanced roadway surrounding rock during the mining process of the working face. The collaborative erosion-control method of releasing-splitting-supporting based on coal mass pressure relief and roof pre-splitting, and to carry out local pressure relief, roof pre-splitting and reinforcement support construction in the whole cycle of the coal working face in a progressive manner, so as to achieve the prevention and control of rock burst in the working face.

Abstract: A collaborative erosion-control method of releasing-splitting-supporting based on coal mass pressure relief and roof pre-splitting provided by the disclosure includes the following steps: step 1, driving into a coal seam to release pressure; step 2, low roof pre-splitting during driving process; step 3, supporting of roadway surrounding rock and support reinforcement; step 4, floor destressing of the roadway; step 5, high roof pre-splitting before mining; step 6, distress sing and supporting of the advanced roadway surrounding rock during the mining process of the working face. The collaborative erosion-control method of releasing-splitting-supporting based on coal mass pressure relief and roof pre-splitting, and to carry out local pressure relief, roof pre-splitting and reinforcement support construction in the whole cycle of the coal working face in a progressive manner, so as to achieve the prevention and control of rock burst in the working face.

Abstract: A three-dimensional dynamic and static load test system for simulating deep roadway excavation and a method thereof are provided, which relates to the technical field of indoor simulation testing in underground engineering. The system includes a mobile platform, a box body, a support frame, a roadway excavation device, and a data monitoring unit. The system and method of the disclosure can reproduce the whole process of roadway excavation, simulate the multi-directional loading of deep roadway, and restore the real stress state of deep roadway under the influence of dynamic and static load superimposed disturbance. The problem of insufficient research under the condition of unidirectional static loading and lack of multi-directional dynamic and static loading in current large-scale experimental devices has been solved, and the stress and deformation of the surrounding rock of the roadway are reflected in real-time through the data monitoring unit.

Abstract: An in-situ test device and method for surrounding rock strength of bolt supported roadway is provided. The test device includes a fixing mechanism, a loading mechanism, a measuring mechanism and a control system. The loading mechanism includes a hydraulic pump and a plunger pump, the hydraulic pump drives the plunger pump to work and controls the lifting speed of the loading cylinder; the measuring mechanism includes an infrared ranging unit and a wireless pressure monitoring unit; the control system controls the work of the loading mechanism and processes the monitoring data. The test device is directly installed in the roadway and fixed with the bolt. The device is loaded after leveling, the device is disassembled after the monitoring data are obtained, and the in-situ test for the surrounding rock strength of the bolt supported roadway is completed. The steps are simple and adaptable.

Abstract: An in-situ test device and method for surrounding rock strength of bolt supported roadway is provided. The test device includes a fixing mechanism, a loading mechanism, a measuring mechanism and a control system. The loading mechanism includes a hydraulic pump and a plunger pump, the hydraulic pump drives the plunger pump to work and controls the lifting speed of the loading cylinder; the measuring mechanism includes an infrared ranging unit and a wireless pressure monitoring unit; the control system controls the work of the loading mechanism and processes the monitoring data. The test device is directly installed in the roadway and fixed with the bolt. The device is loaded after leveling, the device is disassembled after the monitoring data are obtained, and the in-situ test for the surrounding rock strength of the bolt supported roadway is completed. The steps are simple and adaptable.

Abstract: The present invention discloses a deformation controllable compression ring-based mechanical test system for rocks with variable stiffness and a test method thereof, which comprises a loading device, a variable stiffness regulating device, a data monitoring system and a controlling system; the energy storing spring in the loading device allows the rebounding direction of the loading device to be contrary to the strain direction of the test-piece, which eliminates the energy supplement of the loading device to the test-piece and realizes the loading of an oversized stiffness on the test system; the variable stiffness regulating device precisely regulates the loaded stiffness by regulating the loaded stiffness of the test system according to test requirements, which realizes the test of loading different stiffness on the same test system and avoids the influences of differences to loading parameters between different test systems on the test results.

Abstract: The disclosure provides a variable dip fault slip simulation test method, which relates to the technical field of indoor simulation test of underground engineering. The variable dip fault slip simulation test method of the disclosure adopts a sample device and a loading device, which includes the following steps: Step 1. sample preparation; Step 2. sample assembly; Step 3. loading preparation; Step 4. sample loading. The variable dip fault slip simulation test method of the disclosure can prepare rock like samples with different dip interfaces, simulate the slip failure process of faults with different dip angles, as well as the normal dip slip and reverse dip slip of faults, facilitate the operation of slip simulation test, and collect test data automatically and accurately.

Abstract: The present invention discloses a deformation controllable compression ring-based mechanical test system for rocks with variable stiffness and a test method thereof, which comprises a loading device, a variable stiffness regulating device, a data monitoring system and a controlling system; the energy storing spring in the loading device allows the rebounding direction of the loading device to be contrary to the strain direction of the test-piece, which eliminates the energy supplement of the loading device to the test-piece and realizes the loading of an oversized stiffness on the test system; the variable stiffness regulating device precisely regulates the loaded stiffness by regulating the loaded stiffness of the test system according to test requirements, which realizes the test of loading different stiffness on the same test system and avoids the influences of differences to loading parameters between different test systems on the test results.

Abstract: The disclosure provides a variable dip fault slip simulation test method, which relates to the technical field of indoor simulation test of underground engineering. The variable dip fault slip simulation test method of the disclosure adopts a sample device and a loading device, which includes the following steps: Step 1. sample preparation; Step 2. sample assembly; Step 3. loading preparation; Step 4. sample loading. The variable dip fault slip simulation test method of the disclosure can prepare rock like samples with different dip interfaces, simulate the slip failure process of faults with different dip angles, as well as the normal dip slip and reverse dip slip of faults, facilitate the operation of slip simulation test, and collect test data automatically and accurately.

Abstract: A rock mechanics test system with impact loading-confining pressure unloading and its usage method. The test system includes bearing frame unit, axial compression loading unit, impact loading unit and confining pressure loading unit. The bearing frame unit includes pedestal, column and cross beam. The column is vertically installed on both sides of the upper surface of the pedestal, and the cross beam is horizontally fixed on the upper part of the column. The axial compression loading unit is fixed at the middle position of the upper surface of the pedestal and is used to exert the axial bottom-up pressure to the sample. The impact loading unit is fixed on the cross beam and is used to exert the axial top-down impact load on the sample.

Abstract: A device includes a pressure measuring segment, a connecting rod, a hydraulic pump, a pressure gauge, a high-pressure oil pipe, a pressure control valve, a tray, a push rod and a connection casing. The pressure measuring segment is on the connecting rod, a front end of the push rod is connected with the connecting rod, the tray is at a rear end of the push rod, the connection casing is connected with the tray. The pressure measuring segment includes a main pipe, a hydraulic bladder, a fixing ring, a barrier sheet, an outer pillow housing and a connection sleeve. Both ends of the hydraulic bladder are sleeved on the main pipe, an oil inlet is in communication with the hydraulic bladder, the outer pillow housing is sleeved on the main pipe, the connection sleeve is wrapped around the outer pillow housing.

Abstract: The present disclosure provides a true triaxial tester with adjustable loading stiffness and a test method, relating to the technical field of rock mechanics. The tester includes a first principal stress variable stiffness loading apparatus, a second principal stress variable stiffness loading apparatus, a third principal stress loading apparatus, a monitoring system, and a control system. The monitoring system includes a stiffness sensor, a pressure sensor, and a displacement sensor. Loading stiffness in a first principal stress direction and a second principal stress direction is adjustable. The tester has the following advantages: it has fixed loading stiffness, can complete stiffness loading of one side being free and five sides being variable, and is easy to operate.

Abstract: It discloses a grouting bolt-cable composite beam and supporting method for advanced support of fractured surrounding rock in deep coal mines. The quadrate plates are fixed at both ends of the steel beam, the anchor cable holes are arranged in the center of the steel beam and the quadrate plates, and the diameter of anchor bolt holes should be larger than that of the grouting cables. There are four anchor bolt holes on each quadrate plate, and each anchor bolt hole corresponds to a anchor plate, the horizontal surface of the anchor plate is close to the quadrate plate, and the arc parts of the four anchor plates are all facing the center of the quadrate plate.

Abstract: The present disclosure provides an inner and outer framework combined variable stiffness rock mechanics tester and a testing method, relating to the technical field of rock mechanics. The tester includes a stiffness adjusting apparatus, a test loading apparatus, a monitoring system, and a control system. During a test, according to monitoring data, the load of the stiffness adjusting cylinder is controlled through the control system, and the displacement of the inner top beam is adjusted in real time, to ensure that the loading stiffness reaches a design value and remains constant, which solves the technical problem that the loading stiffness of the rock mechanics tester cannot be quantitatively adjusted, and is easy to operate.

Abstract: The present disclosure provides a true triaxial tester with adjustable loading stiffness and a test method, relating to the technical field of rock mechanics. The tester includes a first principal stress variable stiffness loading apparatus, a second principal stress variable stiffness loading apparatus, a third principal stress loading apparatus, a monitoring system, and a control system. The monitoring system includes a stiffness sensor, a pressure sensor, and a displacement sensor. Loading stiffness in a first principal stress direction and a second principal stress direction is adjustable. The tester has the following advantages: it has fixed loading stiffness, can complete stiffness loading of one side being free and five sides being variable, and is easy to operate.

Abstract: An anchor bolt length determination method based on monitoring of a roof rock stratum horizontal extrusion force includes drilling a borehole in the middle of a roadway roof to determine a surrounding rock fracturing scope by a borehole television. The method includes selecting the number and locations of horizontal extrusion force measuring points according to the surrounding rock fracturing scope. The method includes monitoring and recording a change of the horizontal extrusion force over time in the borehole by a device for monitoring a roof rock stratum horizontal extrusion force. The method includes selecting a location with the largest horizontal extrusion force as a center of a anchoring segment of an anchor bolt to determine a distance between the anchoring center and the roof. The method includes calculating a total length of the anchor bolt.

Abstract: The present disclosure provides an inner and outer framework combined variable stiffness rock mechanics tester and a testing method, relating to the technical field of rock mechanics. The tester includes a stiffness adjusting apparatus, a test loading apparatus, a monitoring system, and a control system. During a test, according to monitoring data, the load of the stiffness adjusting cylinder is controlled through the control system, and the displacement of the inner top beam is adjusted in real time, to ensure that the loading stiffness reaches a design value and remains constant, which solves the technical problem that the loading stiffness of the rock mechanics tester cannot be quantitatively adjusted, and is easy to operate.