考虑损伤与结构面影响的高应力地下洞群开挖反馈分析  

Back Analysis on Rockmass Deformation of Underground Cavern Excavation in High In-situ Stress Field by Considering the Effect of Damages and Weak Planes

作　　者：杨云浩[1] 王仁坤[1] 肖平西[1] 李治国[1] 

机构地区：[1]中国水电顾问集团成都勘测设计研究院,四川成都610072

出　　处：《水力发电》2013年第10期18-22,共5页Water Power

摘　　要：针对猴子岩水电站地下厂房区高地应力环境和围岩岩性及其结构特点,将考虑损伤与结构面影响的弹塑性应变软化模型应用于厂房洞群的开挖反馈分析中。分析结果表明,由于岩体内层理不发育,Ⅲ、Ⅳ级结构面仅局部发育且无明显的优势方位,围岩损伤特征主要与地应力场有关,拱肩和边墙是损伤重点发生部位;结构面显著地影响了围岩变形量值,相比于不考虑结构面的情况,两者围岩位移相对差最大可达34.43%;考虑损伤与结构面的双重影响后,除主厂房顶拱浅表层个别测点外,多数测点的位移计算值与监测值吻合较好。To investigate the effects of high in-situ stress and weak planes on the deformation characteristics and damage zone around the underground powerhouse caverns in Houziyan Hydropower Station, the displacement-based back analysis is conducted by using a strain-softening constitutive model which is capable of describing induced orthotropic damage and accounting for the presence of an orientation of weak plane The results of back analysis show that： （a） Due to the fact that weak planes in rockmass are not in favor of a single specific orientation, the damage characteristic of surrounding rockmass is mainly related to the in-situ stress field rather than the weak planes and heavy damages occur at the flank of arch and side walls; （b） the deformations of surrounding rockmass accounting for or ignoring the effect of weak plane are compared with each other and the maximum relative deviation is 34.34% which imply that the deformation is significantly affected by the occurrence of weak plane; and （e） the calculated displacements after considering the combined effect of damages and weak planes approximately agree with those of field measurement at most of measuring points except for that located at center of powerhouse cavern arch.

关 键 词：地下洞室 结构面 正交异性损伤 弹塑性应变软化模型 反馈分析 

分 类 号：TU457[建筑科学—岩土工程] TV731.6[建筑科学—土工工程]