Analysis of the Optimum Support Dismantling Scheme for Shallow Bored Subway Stations in a Soil-Rock Compound Stratum
(1 College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100; 2Beijing Urban Engineering Design & Research Institute Co. Ltd., Beijing 100037)
Abstract：
In tunnel construction, dismantling the temporary strut or steel support will break the original balance of the structural system, especially in shallow tunnels with large sections, which may cause a safety accident by excessive deformation of the primary support or the local overloaded internal force if dismantling of the temporary support is performed in an improper way and at an improper time. A large-span shallow bored subway station in a soil-rock compound stratum is used as an example in this paper to simulate the process of dismantling the longitudinal temporary support in a large-section tunnel by a 3D model, and the effects of different dismantling sequences and one-time demolition lengths on the tunnel structure are analyzed. The analysis results show that the effect of alternating the dismantling sequence and the one-time demolition length of 6 m on factors such as crown settlement and surface subsidence is comparatively small. Additionally, a recommended value for controlling standards of surface subsidence induced by dismantling is presented on the basis of numerical calculations, providing a reference to similar projects.
.Analysis of the Optimum Support Dismantling Scheme for Shallow Bored Subway Stations in a Soil-Rock Compound Stratum[J] MODERN TUNNELLING TECHNOLOGY, 2015,V52(5): 131-137
2015, Vol. 52 