Study On Stability Of The Doubled-arch Tunnel In The Shallow Slanting Cover

In recent years, with the incessant development of thruway, the quantities of tunnel increase fast. The multi-arch tunnel have been adopted more and more because of it's advantage, such as fluent appearance, well using of space, less construct area, convenient to connecting to the way, and so on. With the incessant development of design theory of tunnel timbering, New Austrian Tunneling Method become the representative of present-day timbering design theory, especially the application of field monitoring measurement combined with theory analysis, which give birth to a new design method——information design method. This is a method fit for underground construction and modern technology. Field monitoring, dynamic design, information construction have been became the developing direction of tunnel and underground construction.Based on the field monitoring measurement and numerical simulation for YuLingguan twin-arch Tunnel, the author try to analyze the application of field monitoring measurement, dynamic design, information construction on the weak wall-rock sector tunneling. This article has analyzed stress; strain and stability of tunnel wall-rock sector and geological condition during the excavation. The author has analyzed the construction mechanics of lean stress weak wall-rock sector multi-arch tunnel, which is based on the field monitoring measurement and numerical simulation. In addition, the author summarized the basic principle and basic character of the field monitoring measurement for YuLingguan tunnel, and analyzed the stress variety character of first timbering and second timbering. Assume several different construction order, analyze and compare the stress of tunnel, first timbering, second timbering and displacement condition, in order to choose the better construction order and optimize design. Analyze the danger during the excavation, describe the function of field monitoring measurement in the excavation when encounter danger. Use 3-D numerical simulation analyzes the cause of danger and the stress condition after deal with the danger.