A constitutive model and numerical simulation for zonal disintegration of surrounding rock in deep roadway

In comparison to shallow roadway, disintegrative zone and un-disintegrative zone appear several times alternately in the surrounding rock of deep roadway, which is called Zonal Disintegration. Now, no agreement is established about the mechanism of zonal disintegration in deep roadway. First, based on traditional Nishihara model, the second power strong rheological model is constructed, which can describe full stage creep process of rock, and accelerated creep equation of rock mass is obtained. Second, according to evolution process on zonal disintegration of deep rock, maximum tensile stress criterion, shear failure criterion and the fourth strength criterion are determined as failure judgment criteria of deep rock mass with the priority level decreased. Against the background of mining and geological conditions of 4417 transport roadway, zonal disintegration simulation of surrounding rock is carried out in this roadway with FLAC-3D numerical simulation software, judgment criteria and constitutive equation got in this paper as accelerated creep equation of rock mass, and simulation results are the same as those of field tests.