【摘要】 为分析大岗山水电站地下厂房洞室群施工开挖过程中围岩的稳定性状况,采用多元回归分析方法反演了厂区初始地应力场,提出了厂区初始地应力的分布函数;根据建立的地下厂房三维数值计算模型,获得洞室开挖后围岩位移场、应力场和塑性区的变化规律。计算结果表明:大岗山地下厂房洞室群开挖后围岩整体是稳定的,洞周分布的软弱岩脉是影响围岩稳定的关键因素,在地下厂房施工过程中,必须对软弱岩脉和开挖暴露的破碎带进行超前注浆加固处理。计算成果有效指导了工程的设计与施工。更多还原

【Abstract】 Dagangshan hydroelectric power station is a large scale hydropower project developed recently on the Dadu River.In order to analyze the stability of surrounding rock of underground powerhouse caverns during construction excavation,the multiple regression analysis method is employed to inverse the initial geostress field of plant zone,and the functions of initial stress distribution are proposed.The variation regularities of displacement field,stress field and plastic zone of underground powerhouse caverns after excavation are obtained according to the established 3-D numerical computational model.Computing results show that the surrounding rock of Dagangshan underground caverns is stable as a whole after excavation.The weak rock veins are key factors influencing the stability of surrounding rock of underground powerhouse.The soft rock veins and fracture zone must be pre-grouted and reinforced during construction.These computation conclusions have guided the design and construction of the project effectively.更多还原