Abstract--This second report by the ITA Working Group on General Approaches to the Design of Tunnels presents international design procedures [or tunnels. In most tunnelling projects, the ground actively participates in providing stability to the opening. Therefore,the general approach to the design o[ tunnels includes site investigations, ground probings and in-situ monitoring, as well as the analysis of stresses and de[ormations. For the latter, the different structural design models applied at present--including the observational method--are presented. Guidelines [or the structural detailing of the tunnel lining and national recommendations on tunnel design are also given. It is hoped that the information herein,based on experiences [rom a wide range o[ tunneUing projects, will be disseminated to tunnel designers throughout the world.
这是摘要，看看需要的就下
