Influence of Environmental Variation of Underground Excavation on Support Safety
It is very important for engineering design to study the excavation and support time of underground caverns based on the New Austrian Tunneling Method (NATM). The sensitivity of surrounding rock of underground wall and in-situ stress of field are analyzed by Hoek-Brown strength criterion, which is widely used in geotechnical engineering. The results show: With the increase of burial depth, the magnitude of in-situ stress increases, the safety factor of structure becomes a form of power function, with the increase of GSI, the safety factor is reduced first and then increased by polynomial form change, with the increase of rock mi, the safety factor gradually increased, but the range of change is not obvious, with the increase of the rock disturbance factor D, the safety factor gradually increases. Note that, with the increase of these parameters, and sometimes the safety factor to show an increasing trend, but at this time should pay attention to the deformation of the surrounding rock has been great, the surrounding rock prone to destabilization damage.