Research on the deformation and failure mechanism of soft rock roadways and supporting technology based on triaxial rheological experiments in site

The soft rock deformation and failure are the serious disasters in soft rock roadway supporting in the deep mining of coal mine.Based on the triaxial rheological experiments in site of mudstone in Liuzhuang mine and numerical modeling,the deformation and failure mechanism of soft rock roadways and its supporting technology were analyzed.The damped least square method (Marquardt method) was used to the indirect gradual linearization analysis and the creeping constitutive equations were formed by using the nonlinear rheological model.Then the reasonable supporting mode of deep soft rock roadway in Liuzhuang mine was obtained.That is,adopting the inverted arch and fully closed construction mode,keeping the bolt drilling and installation orientation in the major chamber of bedded tunneling vertical to the bedding plane and supporting roadway by bolting and grouting reinforcement floor