Research On Tunnel Dynamic Response Law Influenced By Mining Excavate Area

In recent years as the mining excavation scale increasing, coal seam excavation movement caused the tunnel stress distribution again, coal bed repeatedly excavation movement on the stability of underground tunnel and its supporting problem study became the main key factor to the development of the coal industry.This paper make a study of the influence on bottom transportation tunnel, which top part of Beichen transportation tunnel which is200m underground.and gets conclusions that tunnel deformation has a connection with the mining height of coal and the vertical distance of mining area, mining height is in inverse proportion with the deformation of tunnel, and vertical distance has more influence on deformation than what mining height get. these conclusions are all on the basis of using FLAC3D as analysis program to analysis the9groups scheme of numerical simulation with different mining height and different vertical distance, and the parameters of tunnel surrounding rock are get from laboratory physical mechanic experiment. Laneway stress reduces by the distance of coal digging getting far. and there is a peak in this change period. Accounting for the inclined of runnel, the characters of the spread of plastic area of tunnel mainly obvious on left arch of tunnel, left working lope of tunnel and left base angle of tunnel. For the spread characteristics of tunnel plastic area can be the theoretical support for tunnel support, we can get clear that, during the period of coal digging, for the short distance between tunnel and digging area, bottom tunnel uplift and even move to the area which is well dig. According to the actual monitoring results can be seen, before coal seam excavation, tunnel displacement move to tunnel section. Based on the numerical simulation and monitoring material, put out an appropriate roadway supporting scheme, and applied to the practical project.