Face Stability Analysis of Circular Tunnels Driven by a Pressurized Shield
Face Stability Analysis of Circular Tunnels Driven by a Pressurized Shield
复制标题
DOI：
10.1061/(asce)gt.1943-5606.0000194
复制
发表时间：
2010-01-01
影响因子：
3.9
通讯作者：
Soubra, Abdul-Hamid
中科院分区：
文献类型：
--
作者：
Mollon, Guilhem;Dias, Daniel;Soubra, Abdul-Hamid
本文的目的是确定加压盾构法圆形隧道的工作面坍塌压力。分析是在极限分析理论的运动学方法框架下进行的。它基于平移三维多块失效机制。与现有的基于摩擦土情况下的极限分析机制相比，本破坏机制具有显著的优势：它考虑了整个圆形隧道工作面，而不仅仅是这个圆形区域的内接椭圆。这是通过使用空间离散化技术实现的。因此，三维破坏面是“逐点”生成的，而不是简单地使用现有的标准几何形状，如圆锥体或圆柱体。数值结果表明，由三个块组成的多块机制在计算时间和结果精度之间取得了很好的折衷。该方法显著地改进了其他运动学方法给出的崩塌压力的最佳解。给出了摩擦粘性土在岩土工程中的实际应用设计图。
The aim of this paper is to determine the face collapse pressure of a circular tunnel driven by a pressurized shield. The analysis is performed in the framework of the kinematical approach of limit analysis theory. It is based on a translational three-dimensional multiblock failure mechanism. The present failure mechanism has a significant advantage with respect to the existing limit analysis mechanisms developed in the case of a frictional soil: it takes into account the entire circular tunnel face and not only an inscribed ellipse to this circular area. This was made possible by the use of a spatial discretization technique. Hence, the three-dimensional failure surface was generated "point by point" instead of simple use of existing standard geometric shapes such as cones or cylinders. The numerical results have shown that a multiblock mechanism composed of three blocks is a good compromise between computation time and results accuracy. The present method significantly improves the best available solutions of the collapse pressure given by other kinematical approaches. Design charts are given in the case of a frictional and cohesive soil for practical use in geotechnical engineering.