Mechanical Characteristics And Experimental Study Of Anchorage Combined Support For Advanced Support In Fully Mechanized Face

Effective supporting for the advanced supporting area of the mining roadway in the fully mechanized face is an important guarantee to ensure efficient and safe mining.Although a lot of work has been done on the advanced supporting of the mining roadway at home and abroad,there is no clear research on the combined supporting mechanism for roadway surrounding rock of the advanced hydraulic supporting group and the anchoring equipment.By using the combination of the theoretical modeling,the numerical simulation,the combined verification of laboratory similar simulation experiments and field experiments,the mechanical relationship between the advanced hydraulic supporting group and the roadway surrounding rock under the supporting condition of the roadway anchoring equipment has been studied in the paper,the main research contents are as follows:Aiming at the mutual influence on the combined supporting process of the advanced hydraulic supporting group and the anchoring equipment,considering the elastic deformation characteristics of roadway roof,the roadway roof was viewed as an infinite half-space elastomer,the top beam of the advanced hydraulic supporting group and the anchoring equipment tray were viewed as the rigid bodies.The mechanical models of contact between the top beam and the roadway roof and of the contact between the tray and the roadway roof were established respectively.According to the superposition principle,the contact mechanics model of the advanced hydraulic supporting group-anchor combined supporting roof was established.The model was solved by using the two-repetition Gauss-Lergen integral method,the distribution of displacement and stress gradient of the roof of the combined supporting roadway was obtained.Aiming at the poor stability of the roof under equal-strength supporting of the advanced hydraulic supporting group,the characteristics of roadway roof was described by using the plate theory.The advanced hydraulic support was equivalent to an elastic support with a stiffness of K.The mechanical model of the advanced hydraulic supporting group-anchor combined supporting elastic plate was established based on the energy functional theory.The anchoring potential and penalty function were used to introduce the anchoring equipment function and model boundary into the system energy functional.The displacement and stress changes of the roadway supporting roof of anchoring supporting and advanced hydraulic supporting group under equal-strength supporting and four kinds of non-equal-strength supporting were analyzed respectively.On this basis,the "secondary Fourier" non-equal-strength combined supporting scheme of the advanced hydraulic supporting group-anchor was proposed.Based on similar simulation theory,a similar experimental model was established according to the 1:40 geometric similarity constant to simulate the 15106 working face for roadway advanced supporting in Wenjiazhuang Mine of Pingshu Company in Yangquan,Shanxi province by using the 3D Similar Simulation Experiment Platform of the Key Laboratory of Mine Subsidence Disaster Prevention of Liaoning Provincial Education Department.By simulating the compensating buried depth load and the confining pressure loading system by the top loading system,the simulated experiments were carried out by anchoring support,equal-strength supporting and 2 kinds of non-equal-strength combined supporting methods.By comparing the stress and displacement changes of roadway surrounding rock under different supporting modes,the accuracy of the mechanical model of the advanced hydraulic supporting group-anchor combined supporting elastic plate was verified,and the rationality of the proposed "secondary Fourier" non-equal-strength combined supporting scheme was verified.In 15106 working face by roadway advanced supporting in Wenjiazhuang Mine of Pingshu Company in Yangquan,Shanxi,the non-equal strength and equal strength combined supporting roadway surrounding rock experiment of the "secondary Fourier" advanced hydraulic supporting group-anchor supporting were carried out.The correctness of the theoretical model and the validity and correctness of the "secondary Fourier" non-equal-strength combined supporting scheme were verified.The research results of the paper provide the theoretical basis for the effective maintenance and management of the mining roadway,the highway tunnel and the similar roadway surrounding rock in coal mine underground mining face,and provide the theoretical support for the design and intelligent control of advanced supporting equipment,and of certain theoretical significance and engineering value.