复杂条件下大型地下洞室群的变形稳定性分析

本文结合某水电站工程建设实例,在现场地质调查和地勘资料分析的基础上,建立了能够反映工程区陡峻地貌、软弱断层和高地应力环境条件下的计算模型。以地应力实测结果为依据,采用线弹性方法反演了初始地应力场,在此基础上,通过编制程序施加应力的方法简化数值模型,采用弹塑性方法对地下厂房进行了三维模拟,分析结果表明:相邻洞室之间的围岩,尤其是主厂房与尾水调压室之间存在局部的塑性破坏,破坏部位主要在洞室腰部和顶角部位,应力集中则主要在顶角部位。本文的建模方法和分析结果,对于类似工程将具有一定的借鉴意义。

DEFORMATION AND STABILITY ANALYSIS OF LARGE-SCALE UNDERGROUND CAVITY GROUP UNDER COMPLICATED GEOLOGICAL CONDITIONS

Based on the investigation and geologic exploration information of a hydroelectric power station,the authors set up a computational model which reflects project area steep topography,soft fracture,elaborate underground powerhouse,high earth stress and environmental condition as well.According to earth stress actual measurement results,the initial stress field is played back by linear-elasticity method.To simplify the numerical model,the author adopts an adding stress program and analyses the large-scale caverns in three-dimensional modeling by elastic-plasticity method.The results show clearly that the wall rock between the neighbor cavities,in especial between main power house and tail water houses,the rock wall local plastic failure and destroy region mostly at cavity waist and top angle region,while the stress concentration mostly at top angle region.Both the modeling method and analytic result have a reference sense toward analogy engineering.