Response models of weakly consolidated soft rock roadway under different interior pressures considering dilatancy effect
来源期刊：中南大学学报(英文版)2013年第12期
论文作者：赵增辉 WANG Wei-Ming(王渭明) WANG Lei(王磊)
文章页码：3736 - 3744
Key words：weakly consolidated soft rock roadway; dilatancy effect; modulus damage coefficient; cave interior pressure; response model
Abstract: Surrounding rocks of weakly consolidated soft rock roadway show obvious strain softening and dilatancy effects after excavation. A damage coefficient concerning modulus attenuation was defined. Response models of stress and displacement of surrounding rock of soft rock roadway and analytical expressions to calculate plastic zones under different interior pressures and non-uniform original rock stresses were derived based on damage theories and a triple linear elastic-plastic strain softening model. Influence laws of dilatancy gradient on damage development, distributions of stresses and displacement in plastic region were analyzed. Interior pressure conditions to develop plastic region under different origin rock stresses were established and their influences on plastic region distribution were also discussed. The results show that the order of maximum principle stress is exchanged between σθ and σr with the increase of interior pressure P0, which causes distributions of plastic zone and stress shift. Dilatancy effect which has great influences on the damage propagation and displacements in plastic region has little effect on the size of plastic region and stress responses. The conclusions provide a theoretical basis for a reasonable evaluation of stability and effective supporting of weakly consolidated soft rock roadway.
ZHAO Zeng-Hui(赵增辉)1 , WANG Wei-Ming(王渭明) 2, WANG Lei(王磊)2
(1. College of Science, Shandong University of Science and Technology, Qingdao 266590, China;
2. College of Civil Engineering, Shandong University of Science and Technology, Qingdao 266590, China)
Abstract:Surrounding rocks of weakly consolidated soft rock roadway show obvious strain softening and dilatancy effects after excavation. A damage coefficient concerning modulus attenuation was defined. Response models of stress and displacement of surrounding rock of soft rock roadway and analytical expressions to calculate plastic zones under different interior pressures and non-uniform original rock stresses were derived based on damage theories and a triple linear elastic-plastic strain softening model. Influence laws of dilatancy gradient on damage development, distributions of stresses and displacement in plastic region were analyzed. Interior pressure conditions to develop plastic region under different origin rock stresses were established and their influences on plastic region distribution were also discussed. The results show that the order of maximum principle stress is exchanged between σθ and σr with the increase of interior pressure P0, which causes distributions of plastic zone and stress shift. Dilatancy effect which has great influences on the damage propagation and displacements in plastic region has little effect on the size of plastic region and stress responses. The conclusions provide a theoretical basis for a reasonable evaluation of stability and effective supporting of weakly consolidated soft rock roadway.
Key words:weakly consolidated soft rock roadway; dilatancy effect; modulus damage coefficient; cave interior pressure; response model
