渗流作用下深部巷道分区破坏的非欧模型

摘要

深部开采过程中巷道围岩呈现分区破坏的特点.针对煤与瓦斯突出、底板破坏等实际工程问题获得了静水压力渗流作用下深部巷道的非欧模型应力分布解.新应力解由两部分组成:一部分是经典解,另一部分是非欧解.运用Mohr-Coulomb屈服准则作为判断新应力解分布引起分区裂化现象的条件.通过数值计算,获得了下列结论:当渗流压力存在时,深部围岩的分区破坏现象依然存在;远场渗透压力增加减小了靠近巷道的环向应力,且井壁渗透压力对巷道的环向应力的影响较小;在远场渗透压力作用下,孔隙度的增加降低了巷道的环向应力;运用Mohr-Coulomb屈服准则,估算了破坏区的位置和宽度;利用建立的有渗流作用的非欧模型解释了煤炭开采过程中的分区破坏现象.研究结果可为理解渗流作用下深部围岩分区破坏提供参考.%In the process of deep mining,roadway surrounding rock presents zonal failure characteristic.The hydro-static non-Euclidean stress distribution solution of deep roadway under permeation action is obtained aiming at coal and gas outburst,floor failure and other practical engineering problems.The new stress solution consists of two parts:one is the classical solution;the other one is the non-Euclidean solution.The Mohr-Coulomb yielding criterion is applied for the condition that the new stress distribution causes zonal failure phenomenon.Through the numerical calculation,the following conclusions are obtained:When there is the permeation action,the zonal failure phenomenon still exists for deep surrounding rock;far field permeation pressure reduces the angular stress of roadway,and borehole permeation pressure influences the angular stress very small;under the far field permeation pressure,the increase of porosity reduces the angular stress of roadway;using the Mohr-Coulomb yield criterion,the location and width of the failure zones are estimated;by using the non-Euclidean model under the permeation,the zonal destruction in the process of coal mining is explained.The present study offers a reference to understanding the zonal failure in deep surrounding rock under the permeation action.