A case study on failure of a tunnel intake

摘要

This paper deals with the study of causes of failure of a tunnel during excavation and the design of pre-support system for proceeding the tunneling. The tunnel, 3396m long, driven by full face method, encountered a failure at the intake during the course of tunneling. Soil tests were carried out to identify the type of soil. The most probable reason for the failure was identified .A pre-support system known as pipe roofing or umbrella arch method was suggested to recover from failure and for proceeding the tunneling. It was modelled using Creo Parametric 1.0 and analysed using ANSYS 12.0 software. This paper concludes that pipe roofing is a practically feasible pre-supporting technique recommended at the site for carrying out further excavation by means of conventional method of tunneling.