调压井施工开挖过程稳定性仿真分析

调压井作为水电站建筑物的重要组成部分,其洞室围岩稳定是一个十分重要的问题。本文利用ANSYS软件的生死单元功能模拟调压井的施工开挖状况。通过不同开挖方法的仿真计算,分析施工过程中围岩的稳定性,研究调压井在支护、钢筋混凝土衬砌及围岩共同作用下的工作性能。同时利用反分析方法,根据现场监测数据,反演岩体由于自重产生的初始地应力和材料特性,得到仿真分析所需的基础资料。分析表明,调压井衬砌的内力分布不均匀,局部应力较大;后边坡有一定变形,需要采取加强措施;施工采用分层开挖,有利于围岩的稳定。

Simulated Process Analysis for the Excavating Construction of Surge-Shaft

As an important part of hydropower station ,the stability of surrounding rock of surge shaft is a strikingly important problem. ANSYS software is employed in this paper whose birth and death element is used to simulate the excavating process. Different excavating methods are calculated to analyze the stability of the wall rock and to investigate the work behaviour when the timbering, reinforced concrete lining and wall rock are interacting. At the same time, to calculate the initial earth stress and material property, inverse analysis was used according to the data by inspected and measured on the site. In the end, the basic information for simulated analysis are obtained. The analysis results indicate that the inner force is uneven in the lining and there is a high local stress, the deformation of back slope is more obvious and the slope need to strengthen, excavating construction by separate layers is of benefit to the stability of wall rock.