Design And Research Of Hydraulic Load Test Bench For Rock Burst Sensing While Drilling

In coal mining,the occurrence of rock-burst has caused huge casualties and equipment damage,and borehole pressure relief is an effective method to prevent rock burst.At present,all drilling and pressure relief machines in coal mines need to be manually operated,which seriously threatens the life safety of operators.It is an important task to develop an anti-scour drilling robot for rock burst mines,so as to realize unmanned operation in the pressure relief area.The hydraulic loading device designed in this thesis simulates the high stress environment state of the rock in the coal mine by triaxial pressurizing the rock model,providing experimental conditions for the subsequent experimental research on the stress evolution law and mechanical information response characteristics in the process of drilling high stress surrounding rock,and realizing the identification and extraction of the mechanical information data of the impact hazard characteristics while drilling,thus completing the design of the anti-impact drilling robot.In this thesis,the loading boundary stress value of rock model is 2.0～4.0MPa,which is determined to meet the material ratio based on the composition of proportioning materials and physical similarity simulation;The hydraulic loading device can achieve long-term automatic pressure maintaining effect and speed regulation capability;The hydraulic cylinder loading on each side has synchronous movement.Therefore,the hydraulic loading test-bed for rock burst sensing while drilling in this thesis is designed and studied.In this thesis,the structure of the loading test bench is designed according to the requirements,and the different thickness sizes of the selected stress plates are simulated and compared through the ANSYS simulation software,so as to continuously optimize the frame structure of the test bench.Finally,the appropriate test bench structure is determined while considering cost saving;This thesis designed a pressure maintaining and speed regulating circuit and made a schematic diagram of the hydraulic system by met the loading requirements and the performance requirements of pressure maintaining and speed regulating,and then introduced the principle of pressure maintaining and speed regulating,and selected the model of hydraulic components through calculation;The hydraulic simulation software AMESim is used to model and simulate the bypass type speed regulating valve elements and the speed regulating circuit and pressure maintaining circuit of the hydraulic system.The curves obtained from the analysis and simulation verify the correctness of the modeling of the speed regulating elements and the two circuits.The simulation data are basically consistent with the designed values of the hydraulic system,which verifies the rationality of the hydraulic system designed of the test bench,It provided the reliability verification for the research and performance improvement of the hydraulic system of the rock burst while drilling sensing test-bed,and provided the experimental conditions for the development of the anti-impact drilling robot for the rock burst mine.In the structural designed of the test bench,the screw connection structure between the piston rod of the hydraulic cylinder and the rock pressure plate is designed based on the stress analysis of the rock model,so that the test bench can be easily operated by repeatedly pressurizing the rock model.At the same time,it is necessary to maintain the integrity of the roadway before drilling by the drilling rig.Whether the roadway is excavated first and then the rock is pressurized,or the rock is pressurized first and then the roadway is excavated,it will produce irregular roadway and increase the difficulty of construction,which is not conducive to the stress experimental study of the subsequent roadway model.Therefore,this thesis proposed a method to maintain the integrity of the roadway model,so that the drilling experiment can be carried out smoothly,and more accurate roadway experimental data can be obtained.Figure [71] Table [19] Reference [68]...