National Key Lab of Deep Geomechanics and Underground Engineering China University of Mining and
Technology(Bejing)

为了研究深部软岩巷道围岩因吸水软化和强度降低而造成巷道变形破坏严重的主要原因,以鹤岗矿区南山煤矿深部软岩巷道为工程背景,通过对现场巷道典型围岩取样,进行了岩石室内吸水和强度软化实验,试验结果表明:南山矿深部砂岩吸水量随时间的变化分为急速增长阶段、非线性减速增长阶段、等速增长3个阶段;强度软化随吸水时间变化也分为3个阶段,即强度迅速衰减阶段、减速衰减阶段和强度稳定阶段,拟合曲线表明深部砂岩强度衰减与吸水时间呈指数关系。

In order to obtain the main causes of the serious mine roadway deformation and failure occurred by the water absorption softeningand strength reduced of t he surrounding rock in the deep soft rock roadway,based on the deep soft rock roadway of Nanshan Mine in He-gang Mining Area as an engineering background,with the si te sampling of the typical surrounding rock in the mine roadway,the authorsconducted the rock indoor water absorption test and strength softening test. The experimental re sults showed that the water absorption curveof deep sandstones in Nanshan mine could be divided into three stages,the rapid growth stage ,nonlinear slow growth stage ,an d the con-stant growth stage. The rock softening was obvious with the growth of water absorption and the tested strength curve had three stages,name-ly the sharp decay, slow decay and constant decay stage. The fitting curves showed the exponential relation between strength softening andtime of water absorption,which would provide theor etical basis for the further study on mechanisms of deformation failure and stability con-trol countermeasures to deep soft rock tunnel during excavation.

国家自然科学基金资助项目(51479195,51374214)；中央高校基本科研业务费专项资金资助项目(2009QL06)；