【摘要】 以三峡工程右岸浅埋地下厂房为例,基于施工期变形监测资料及数值模拟分析,结合地质和施工资料,对地下厂房围岩变形特征及其机制进行分析。围岩变形受结构面分布、自然应力场及地形条件等因素影响。由于地下电站区最大水平主应力近垂直于厂房轴线,大跨度高边墙厂房顶拱易产生向上抬起变形,而边墙以近水平向卸荷变形为主,且边墙变形明显较顶拱变形大;与边墙小角度相交的断层主要表现为卸荷张开变形,断层与开挖面之间的岩体变形集中;偏压地形的山峰一侧围岩变形普遍较大。围岩的上述变形特征表明围岩稳定性数值分析中应充分考虑其相关的地质条件,建立如实反映工程实际的地质力学模型是成功的工程实例数值分析的前提。更多还原

【Abstract】 Taking the shallow large underground powerhouse on the right bank of the Three Gorges Project as an exemple,based on the monitored deformation data during excavation and numerical simulation analysis,the deformation characteristics and mechanism of surrounding rock masses are analyzed considering geological data and excavation process. The rock masses deformation is influenced by geological structural planes,natural stress field and landform etc. The crown of the wide span and high wall underground powerhouse is easily uplifted,but the wall mainly deformed in the horizontal direction and larger than the crown because that the maximal horizontal primary stress is almost normal to the axes of powerhouse. The deformation of the faults which smaller angle intersect the wall are mainly composed of the unloading opening displacement,and rock masses deformation is mostly centralized between the fault and excavated surface. The deformation of surrounding rock masses in the side of mountain peak is larger under unsymmetrical pressure at large. The characteristics mentioned above suggest that the correlative geological data must be adequately considered when numerical simulation analysis for evaluation to stability of rock masses,the geo-mechanics model which based on actual engineering condition is the premise of successfully numerical calculation for the example.更多还原