压力隧洞钢筋混凝土衬砌的优化设计方法

Optimization design method for reinforced concrete lining of pressure tunnel

压力隧洞衬砌形式的应用高度依赖于地质和水力条件。衬砌有两种类型,即混凝土衬砌和钢衬砌,但钢衬砌是最昂贵的形式之一。为了减少隧洞中的钢衬砌长度,采用能防止围岩渗水的混凝土衬砌是较好的选择。本文重点研究了基于混凝土衬砌临界配筋率的压力隧洞衬砌水损失限制问题。为了评价内水压力对混凝土衬砌和围岩渗透系数变化的影响,在孔隙流体-应力耦合分析的基础上,利用ABAQUS有限元软件对钢筋混凝土衬砌进行了模拟。结果表明,尽管临界配筋率在控制渗流和水损失方面起着重要作用,但仅仅依赖于临界配筋率是不够的,还应考虑混凝土衬砌中钢筋的合理布置。

The application of pressure tunnel lining form highly depends on geological and hydraulic conditions.There are two types of lining,concrete lining and steel lining,but steel lining is one of the most expensive forms.In order to reduce the length of steel lining in tunnel,it is a better choice to use concrete lining which can prevent water seepage from surrounding rock.This paper focuses on the water loss limitation of pressure tunnel lining based on the critical reinforcement ratio of concrete lining.In order to evaluate the influence of internal water pressure on the permeability coefficient of concrete lining and surrounding rock,based on the coupling analysis of pore fluid and stress,the reinforced concrete lining was simulated by ABAQUS finite element software.The results show that although the critical reinforcement ratio plays an important role in controlling seepage and water loss,it is not enough to rely on the critical reinforcement ratio alone,and the reasonable arrangement of reinforcement in concrete lining should also be considered.