Study On Surrounding Rock Stability Of Stope With Access Back-filling Based On Timeliness

Hemushan iron mine belongs to Ma Steel(Group).It is a typical example of soft rock mining engineering.It's extremely complex igneous rock environment has been recognized,weak broken belt and highly development jointed assign among at the surrounding rock which acrossed with high swelling of clay interspersed.The deformation and failure of mining entrance becoming serious along with the time and advance of working face,which shows a significant time and space effects.In underground mining,soft rock roadway with its time and space effects is not to be ignored.For rheological characteristics of soft rock roadway,the ultimate damage is caused of creep deformation rather than insufficient strength.For miscellaneous existed in the mining entrance supporting,based on the oretical analysis and numerical simulation method,from multiple dimensions did the research on surrounding rock stabality control and supporting technology of soft-rock mining entrance based on the timeliness.On this basis,proposed support scheme and apply research results in practice,the paper won the following major findings:(1)Experimental study on basic mechanical properties of rock and filling body.Based on the conventional triaxial compression test,the strength and deformation and failure characteristics of the samples under normal triaxial tests were studied,and the elastic modulus,peak strain and residual Strength and confining pressure,to obtain its basic physical parameters.(2)Experimental study on rock creep mechanics characteristics.Based on the conventional triaxial experiments of rock and rock,the creep test of rock grading is carried out to study the relationship between rock creep rate and confining pressure,and the rock creep.The creep model consistent with the creep law of the mountain rock is established.The regression analysis is carried out by the mathematical software Origin to obtain the rock creep parameters.(3)Based on the FLAC3 D numerical simulation software,the stability of the surrounding rock under different working conditions of the Hemushan Iron Mine is studied,and the displacement evolution law of the surrounding rock under different working conditions is studied.The effects of excavation and recovery sequence on the stability of surrounding rock are studied.The stress,strain and displacement of the surrounding rock are analyzed under different excavation stages.The influence of the interaction effect on the stability of the surrounding rock is analyzed based on the time difference of the stratified filling and mining.(4)Engineering applications.Based on the above research results,the supporting parameters of the Meishan Iron Mine Stope are optimized based on the time delay,and the supporting table based on different surrounding rock and different service years is proposed.Based on the support strategy table,the simulation analysis of the different support types of-235 m road route is carried out to optimize the support parameters of the road,to determine the most suitable support way for the top support to support four bolt support,and passed the field engineering test validation.