Study on Modes and Calculation Method of Stress and Deformation of TunnelPortal Landslide Parallel System
(1. Sichuan Highway Planning, Survey, Design and Research Institute Ltd., Chengdu 610041; 2. China Railway Northwest Research Institute Co., Ltd., Lanzhou 730070; 3. China Railway Landslide Engineering Laboratory, Lanzhou 730070; 4. Provincial Laboratory of Western Environmental Geotechnical Soil and Site Remediation Technology, Lanzhou 730070)
Abstract:
At present, the unified industry standard has not yet been issued in China for the design of tunnel-land? slide engineering. Particularly, there is a lack of corresponding calculation theories for tunnels at the portal-landslide section. Taking the tunnel-portal landslide in the parallel system as the research subject, this paper constructs the corresponding engineering geological model by summarizing the failure characteristics of the tunnel lining in the landslide sections. Considering the residual landslide thrust as the direct cause of the tunnel deformation and failure, the additional load acting on the tunnel structure is obtained by the load transfer mechanism, and the calculation formula for external load on tunnels is derived through superimposing the additional load and the surrounding rock pressure. Using the elastic foundation beam theory, the calculation method for the tunnel internal forces under the action of the landslide thrust is derived, and thus obtaining the modes and calculation theory of stress and defor? mation of the tunnel-portal landslide parallel system. Finally, the rationality of the proposed method is verified through model tests, showing that the method is consistent with actual projects, and providing references for the design of tunnels in portal landslide sections.
ZHAO Jin1 WEN Lina1 WU Honggang2,
3,
4 ZHOU Chici1
.Study on Modes and Calculation Method of Stress and Deformation of TunnelPortal Landslide Parallel System[J] MODERN TUNNELLING TECHNOLOGY, 2022,V59(2): 53-61