STUDY ON THE METHOD OF UNLOADING ZONE DIVISION OF HIGH-STEEP EXCAVATION SLOPE

摘要

Natural rock mass is generally in a stable equilibrium state after suffering lengthy process of geological age. During engineering construction, the rock slope must be excavated, then the ground stress was released, the initial stress equilibrium state was disrupted, and these make the stress field of slope rock mass redistributed. Such redistribution of stress field was undertaken by slope rock mass itself, that is to say, slope was in a unloading mechanical state after excavation. After excavation unloading of rock mass, the quality of rock mass at a certain range will be damaged and deteriorated, and at a certain range the releasing of ground stress made the macro-mechanical parameters of rock mass decreased, therefore this region was usually called unloading zone. Different unloading degree corresponding to different deterioration degree of rock mass mechanical parameters, according to the cause of unloading on excavation rock mass, the method to judge unloading zone of excavation unloading rock mass was presented in this paper. Then simulate the unloading zone of excavation rock mass combined with specific engineering data.