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Analysis of the Impact of Interface Contact Friction on the Seismic Effect of Deeply Buried Shield Tunnels
(1 Key Laboratory of Transportation Tunnel Engineering, Ministry of Education, Southwest Jiaotong University, Chengdu 610031;2 China Construction South Investment Co, Ltd., Shenzhen 518000)
Abstract Based on a quasi-static finite-element numerical model, the law of influence of the seismic effect of a shield tunnel is analyzed for four types of interface contact characteristics, e.g. full contact without slipping, slipping with friction Ⅰ, slipping with friction Ⅱ and full slipping, respectively. Meanwhile, the feasibility and rationality of the quasi-static numerical method is verified by the quasi-static analytical method based on the elastic center method and empty complex function based quasi-static analytical method. The results show that: 1) the quasi-static analysis of circular shield tunnels is feasible with the friction elements simulating interface characteristics under proper boundary conditions; 2) full contact without slipping and full slipping are two ultimate states considering interface contact friction characteristics; 3) under the action of horizontal shear waves, the additional seismic bending moment and axial force distribute as an asymmetrical axis on the axis of 45° and -45°, with a distribution pattern of an asymmetricone; and 4) the additional seismic axial force increases with the increase of the interface friction coefficient,while the additional bending moment decreases with the increase of the interface friction coefficient, which means the friction coefficient has more influence on the axial force than on bending moment.
Abstract：
Based on a quasi-static finite-element numerical model, the law of influence of the seismic effect of a shield tunnel is analyzed for four types of interface contact characteristics, e.g. full contact without slipping, slipping with friction Ⅰ, slipping with friction Ⅱ and full slipping, respectively. Meanwhile, the feasibility and rationality of the quasi-static numerical method is verified by the quasi-static analytical method based on the elastic center method and empty complex function based quasi-static analytical method. The results show that: 1) the quasi-static analysis of circular shield tunnels is feasible with the friction elements simulating interface characteristics under proper boundary conditions; 2) full contact without slipping and full slipping are two ultimate states considering interface contact friction characteristics; 3) under the action of horizontal shear waves, the additional seismic bending moment and axial force distribute as an asymmetrical axis on the axis of 45° and -45°, with a distribution pattern of an asymmetricone; and 4) the additional seismic axial force increases with the increase of the interface friction coefficient,while the additional bending moment decreases with the increase of the interface friction coefficient, which means the friction coefficient has more influence on the axial force than on bending moment.
ZHANG Yu- 1,
2 Yan-Qi-Xiang- 1 He- Chuan- 1 Geng- Ping- 1
.Analysis of the Impact of Interface Contact Friction on the Seismic Effect of Deeply Buried Shield Tunnels[J] MODERN TUNNELLING TECHNOLOGY, 2016,V53(5): 51-55
2016, Vol. 53 