An IBEM solution to the scattering of plane SH-waves by a lined tunnel in elastic wedge space
Zhongxian Liu1, 2, 3, Lei Liu1
1 Tianjin Chengjian University, Tianjin 300384, China
2 Key Laboratory of Soft Soils and Engineering Environmental of Tianjin, Tianjin Chengjian University, Tianjin 300384, China
3 Earthquake Engineering Research Institute of Tianjin, Tianjin 300384, China
An IBEM solution to the scattering of plane SH-waves by a lined tunnel in elastic wedge space
Zhongxian Liu1, 2, 3, Lei Liu1
1 Tianjin Chengjian University, Tianjin 300384, China
2 Key Laboratory of Soft Soils and Engineering Environmental of Tianjin, Tianjin Chengjian University, Tianjin 300384, China
3 Earthquake Engineering Research Institute of Tianjin, Tianjin 300384, China
摘要The indirect boundary element method (IBEM) is developed to solve the scattering of plane SH-waves by a lined tunnel in elastic wedge space. According to the theory of single-layer potential, the scattered-wave field can be constructed by applying virtual uniform loads on the surface of lined tunnel and the nearby wedge surface. The densities of virtual loads can be solved by establishing equations through the continuity conditions on the interface and zero-traction conditions on free surfaces. The total wave field is obtained by the superposition of free field and scattered-wave field in elastic wedge space. Numerical results indicate that the IBEM can solve the diffraction of elastic wave in elastic wedge space accurately and efficiently. The wave motion feature strongly depends on the wedge angle, the angle of incidence, incident frequency, the location of lined tunnel, and material parameters. The waves interference and amplification effect around the tunnel in wedge space is more significant, causing the dynamic stress concentration factor on rigid tunnel and the displacement amplitude of flexible tunnel up to 50.0 and 17.0, respectively, more than double that of the case of half-space. Hence, considerable attention should be paid to seismic resistant or anti-explosion design of the tunnel built on a slope or hillside.
Abstract:The indirect boundary element method (IBEM) is developed to solve the scattering of plane SH-waves by a lined tunnel in elastic wedge space. According to the theory of single-layer potential, the scattered-wave field can be constructed by applying virtual uniform loads on the surface of lined tunnel and the nearby wedge surface. The densities of virtual loads can be solved by establishing equations through the continuity conditions on the interface and zero-traction conditions on free surfaces. The total wave field is obtained by the superposition of free field and scattered-wave field in elastic wedge space. Numerical results indicate that the IBEM can solve the diffraction of elastic wave in elastic wedge space accurately and efficiently. The wave motion feature strongly depends on the wedge angle, the angle of incidence, incident frequency, the location of lined tunnel, and material parameters. The waves interference and amplification effect around the tunnel in wedge space is more significant, causing the dynamic stress concentration factor on rigid tunnel and the displacement amplitude of flexible tunnel up to 50.0 and 17.0, respectively, more than double that of the case of half-space. Hence, considerable attention should be paid to seismic resistant or anti-explosion design of the tunnel built on a slope or hillside.
基金资助:National Natural Science Foundation of China under Grants (51278327) and the Tianjin Research Program of Application Foundation and Advanced Technology (14JCYBJC21900).
通讯作者:
Zhongxian Liu
E-mail: zhongxian1212@163.com
引用本文:
Zhongxian Liu, Lei Liu. An IBEM solution to the scattering of plane SH-waves by a lined tunnel in elastic wedge space[J]. 《地震学报》英文版, 2015, 28(1): 71-86.
Zhongxian Liu, Lei Liu. An IBEM solution to the scattering of plane SH-waves by a lined tunnel in elastic wedge space. Earthquake Science, 2015, 28(1): 71-86.