Arch Tunnel Adaptability And Design

In recent years, the scale of China's transportation infrastructure construction is expanding, and a large number of highways are constructed in the region of west mountains. Rapid development of highway tunnels has been brought about inevitably. Combining needs of layouting line and linking line in the process of design, there has been more multi-arch tunnels. Judging from the current domestic-built multi-arch tunnels, problems are occurred during the construction such as the collapse of surrounding rock in the process of excavation , large cracks on the lining, serious leaking at the lining joints, etal. With multi-arch tunnel appeared in large numbers, the research on the integrated construction technology of multi-arch tunnel is an important topic, and it is urgent.Based on the large number of site investigations, the application conditions and the design method of multi-arc tunnels are elaborated systematically. And Kai Jian Bao No.2 Tunnel as an example, the structure of multi-arch tunnel is studied deeply using finite element program on the basis of site measurement. The main work of this thesis are the followings:1,Analysising construction characteristics of multi-arch tunnel and obtaining the application conditions of it, contrasted with separated tunnel and neighborhood tunnel.2,Analysising characteristics of various structural type of multi-arch tunnel and elaborating their application conditions.3,Elaborating the design method of multi-arch tunnel systematically.4,The spot measurements of Kai Jian Bao No.2 Tunnel are reorganized and analysised.5,Using the structural-load method to compute and analysis the multi-arc tunnel with straight wall and three layers.The conclusion can be reference to the design and construction of similar project.