Research Of Soft Broken Seam Roadway Failure Mechanism In Mine Collapse Column Density

Collapse column density of coal mine soft rock roadway broken support is a top priority issues affecting the efficient support of Coal Mine Safety. Site survey method was adopted density soft thick coal mine collapse columns surrounding rock deformation and failure characteristics of law, preliminary statistics coal roadway damage mechanism, and in the field to select a representative sample, pilot study room, access to basic physical and mechanical properties of coal and rock and post-peak softening; obtain live rock mechanical parameters based rock rating system and construct continuum theory combined with coal and rock crushing peak strain softening after the mathematical model, based on FLAC3D as a platform for secondary development, to build a three-dimensional numerical model Numerical Simulation of the mine collapse column density soft broken seam roadway failure mechanism; fall distribution of the column to get complicated geological conditions by geological prediction method, the tunnel roof collapse column on the hazards controlled by grouting method; optimization of roadway cross-section shape, made arched roadway curved wall, combined with the anchor, nets, spray, steel and other joint supporting the development of methods to control the displacement of surrounding rock; through a lot of on-site monitoring, combined with BP neural network algorithm, a numerical model to build rock displacement prediction; research results provide a theoretical basis and key technical support for similar projects. Research results obtained through the study include:(1) by uniaxial compression tests and triaxial compression tests obtained after mechanical model of coal and rock strength parameters and peaks by nonlinear fitting method and gradient plasticity theory, to build the coal Yanfeng strain softening model.(2) to the continuum theory and plasticity theory, combining rock rating system, get crushed coal and rock strength parameters, and build the broken coal and rock peak strain softening model for in-depth study of coal and rock crushing failure mechanism laid roadway foundation.(3) the use of finite difference software FLAC3D roadway excavation and support for the process simulation, analysis crushing coal roadway deformation and failure characteristics of the law, and the failure mechanism was analyzed; calculated by numerical roadway in the absence of support, anchor when combined support network and shotcrete combined support three kinds of networks supporting way, crushing soft rock roadway deformation trends and the evolution of the stress field.(4) the use of a portable mine detector geology and geological structure of the mine coal seam belt roadway conditions were advanced geological exploration, understanding of the head in front of the belt roadway collapse column geological structure and determine the scope of the implementation of the belt roadway ahead of the pre-grouting solution.(5) the use of bolt dynamometer and Total Station on track roadway bolt actual stress state and the deformation of roadway convergence and dynamic monitoring of BP neural network technology to build the track roadway roadway deformation prediction model of BP, be soft broken roadway deformation prediction analysis;(6) combined with the actual situation of the roadway, industrial test site, design cross-sectional shape and size, to develop an appropriate support parameters, preparation of the corresponding construction organization and analysis of the economic and social benefits.