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Earthquake Engineering and Engineering Vibration 2020年第1期19卷 17-36页

作者： Zhu Jun liang jianwen State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300354China School of Civil Engineering Tianjin UniversityTianjin 300354China

This paper describes a systematic study on the fundamental features of seismic soil pressure on underground tunnels, in terms of its magnitude and distribution, and further identifi es the dominant factors that signifi cantly infl uence the seismic soil pressure. A tunnel embedded in water-saturated poroelastic half-space is considered, with a large variety of model and excitation parameters. The primary features of both the total soil pressure and the pore pressure are investigated. Taking a circular tunnel as an example, the results are presented using a fi nite element-indirect boundary element(FE-IBE) method, which can account for dynamic soil-tunnel interaction and solid frame-pore water coupling. The effects of tunnel stiffness, tunnel buried depth and input motions on the seismic soil pressure and pore pressure are also examined. It is shown that the most crucial factors that dominate the magnitude and distribution of the soil pressure are the tunnel stiffness and dynamic soil-tunnel interaction. Moreover, the solid frame-pore water coupling has a prominent infl uence on the magnitude of the pore pressure. The fi ndings are benefi cial to obtain insight into the seismic soil pressure on underground tunnels, thus facilitating more accurate estimation of the seismic soil pressure.

关键词： seismic soil pressure seismic pore pressure dynamic soil-tunnel interaction water-saturated poroelastic

2.5D scattering of incident plane SV waves by a canyon in layered half-space

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Earthquake Engineering and Engineering Vibration 2010年第4期9卷 587-595页

作者： Ba Zhenning liang jianwen Department of Civil Engineering Tianjin University Tianjin 300072 China Key Laboratory of Coast Civil Structure Safety （ Tianjin University） Ministry of Education

This paper presents a 2.5D scattering of incident plane SV waves by a canyon in a layered half-space by using the indirect boundary element method （IBEM）. A free field response analysis is performed to provide the displacements and stresses on the boundary of the canyon where fictitious uniform moving loads are applied to calculate the Green＇s *** for the displacements and stresses. The amplitudes of the loads are determined by the boundary conditions. The free field displacements are added to the fictitious uniform moving loads induced displacements and the total response is obtained. Numerical calculations are performed for a canyon with homogenous and in one layer over bedrock. The effects of the thickness and stiffness of the layer on the amplification are studied and discussed.

关键词： layered half-space canyon plane SV wave amplification scattering surface layer indirect boundaryelement method

In-plane dynamic Green's functions for inclined and uniformly distributed loads in a multi-layered transversely isotropic half-space

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Earthquake Engineering and Engineering Vibration 2018年第2期17卷 293-309页

作者： Ba Zhenning Kang Zeqing liang jianwen Department of Civil Engineering Tianjin UniversityTianjin 300072China Key Laboratory of Coast Civil Structure Safety(Tianjin University) Tianjin 300072China

The dynamic stiffness method combined with the Fourier transform is utilized to derive the in-plane Green’s functions for inclined and uniformly distributed loads in a multi-layered transversely isotropic（TI）*** loaded layer is fixed to obtain solutions restricted in it and the corresponding reactions forces,which are then applied to the total system with the opposite *** adding solutions restricted in the loaded layer to solutions from the reaction forces,the global solutions in the wavenumber domain are obtained,and the dynamic Green’s functions in the space domain are recovered by the inverse Fourier *** presented formulations can be reduced to the isotropic case developed by Wolf（1985）,and are further verified by comparisons with existing solutions in a uniform isotropic as well as a layered TI halfspace subjected to horizontally distributed loads which are special cases of the more general problem *** deduced Green’s functions,in conjunction with boundary element methods,will lead to significant advances in the investigation of a variety of wave scattering,wave radiation and soil-structure interaction problems in a layered TI *** numerical results are given to investigate the influence of material anisotropy,frequency of excitation,inclination angle and layered on the responses of displacement and stress,and some conclusions are drawn.

关键词： Green's functions transversely isotropic medium multi-layered half-space stiffness method dynamic response

Scattering and diffraction of plane SH-waves by periodically distributed canyons

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Earthquake Engineering and Engineering Vibration 2016年第2期15卷 325-339页

作者： Ba Zhenning liang jianwen Zhang Yanju Department of Civil Engineering Tianjin University Key Laboratory of Coast Civil Structure Safety (Tianjin University) Ministry of Education

A new method is presented to study the scattering and diffraction of plane SH-waves by periodically distributed canyons in a layered half-space. This method uses the indirect boundary element method combined with Green＇s functions of uniformly distributed loads acting on periodically distributed inclined lines. The periodicity feature of the canyons is exploited to limit the discretization effort to a single canyon, which avoids errors induced by the truncation of the infinite boundary, and the computational complexity and the demand on memory can be significantly reduced. Furthermore, the total wave fields are decomposed into the free field and scattered field in the process of calculation, which means that the method has definite physical meaning. The implementation of the method is described in detail and its accuracy is verified. Parametric studies are performed in the frequency domain by taking periodically distributed canyons of semi-circular and semi-elliptic cross-sections as examples. Numerical results show that the dynamic responses of periodically distributed canyons can be quite different from those for a single canyon and significant dynamic interactions exist between the canyons.

关键词： periodically layered uniformly verified decomposed truncation elliptic discretization scattered circular

Diffraction of SH-waves by topographic features in a layered transversely isotropic half-space

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Earthquake Engineering and Engineering Vibration 2017年第1期16卷 11-22页

作者： Ba Zhenning liang jianwen Zhang Yanju Department of Civil Engineering Tianjin University Tianjin 300072 China Key Laboratory of Coast Civil Structure Safety ( Tianjin University) Ministry of Education Tianjin 300072 China

Abstract： The scattering of plane SH-waves by topographic features in a layered transversely isotropic （TI） half-space is investigated by using an indirect boundary element method （IBEM）. Firstly, the anti-plane dynamic stiffness matrix of the layered TI half-space is established and the free fields are solved by using the direct stiffness method. Then, Green＇s functions are derived for uniformly distributed loads acting on an inclined line in a layered TI half-space and the scattered fields are constructed with the deduced Green＇s functions. Finally, the free fields are added to the scattered ones to obtain the global dynamic responses. The method is verified by comparing results with the published isotropic ones. Both the steady-state and transient dynamic responses are evaluated and discussed. Numerical results in the frequency domain show that surface motions for the TI media can be significantly different from those for the isotropic case, which are strongly dependent on the anisotropy property, incident angle and incident frequency. Results in the time domain show that the material anisotropy has important effects on the maximum duration and maximum amplitudes of the time histories.

关键词： wave scattering and diffraction Green's function transversely isotropic SH-waves indirect boundaryelement method

Dynamic soil-tunnel interaction in layered half-space for incident plane SH waves

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Earthquake Engineering and Engineering Vibration 2016年第4期15卷 715-727页

作者： Fu Jia liang jianwen Qin Lin State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Department of Civil Engineering Tianjin University

The dynamic soil-tunnel interaction is studied by indirect boundary element method （IBEM）, using the model of a rigid tunnel in layered half-space, which is simplified to a single soil layer on elastic bedrock, subjected to incident plane SH waves. The accuracy of the results is verified through comparison with the analytical solution. It is shown that soil-tunnel interaction in layered half-space is larger than that in homogeneous half-space and this interaction mechanism is essentially different from that of soil-foundation-superstructure interaction.

关键词： underground tunnel layered half-space plane SH wave indirect boundary element method soil-tunnel interaction site dynamic characteristics

Anti-plane (SH) waves diffraction by an underground semi-circular cavity:analytical solution

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Earthquake Engineering and Engineering Vibration 2010年第3期9卷 385-396页

作者： Luo Hao Vincent W. Lee liang jianwen HNTB Corporation Santa Ana CA 92707-8797 USA Sonny Astani Department of Civil and Environmental Engineering University of Southern California Los Angeles CA 90089-2531 USA Department of Civil Engineering Tianjin University Tianjin 300072 China

Diffraction of a two-dimensional （2D） semi-circular cavity in a half-space under incident SH-waves is studied using the classic wave function expansion method with a new de-coupling technique. This so-called ＂improved cosine half- range expansion＂ algorithm exhibits an excellent performance in reducing displacement residual errors at two rim points of concern. The governing equations are developed in a manner that minimizes the residues of the boundary conditions. Detailed derivation and analysis procedures as well as truncation of infinite linear governing equations are presented. The semi-circular cavity model presented in this paper, due to its simple profile, is expected to be used in seismic wave propagation studies as a benchmark for examining the accuracies of various analytical or numerical methods for mixed-boundary wave propagation problems.

关键词： plane SH waves diffraction, semi-circular cavity half-space improved cosine half-range expansion

Surface motion of a semi-elliptical hill for incident plane SH waves

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Earthquake Science 2011年第5期24卷 447-462页

作者： jianwen liang Jia Fu Department of Civil Engineering Tianjin University Tianjin 300072 China

A closed-form analytical solution of surface motion of a semi-elliptical cylindrical hill for incident plane SH waves is presented. Although some previous analytical work had already dealt with hill topography of semi-circular and shallow circular, our work aims at calculating surface motion of very prolate hill for high incident frequency, and explaining the special vibrating is checked by boundary conditions, numerical results for and some conclusions are obtained. properties of very prolate hill. Accuracy of the solution surface motion of oblate and prolate hills are calculated,

关键词： semi-elliptical hill analytical solution plane SH wave surface motion oblate hill prolate hill Mathieu function high frequency

Diffraction of plane P waves by a canyon of arbitrary shape in poroelastic half-space (Ⅱ): Numerical results and discussion

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Earthquake Science 2009年第3期22卷 223-230页

作者： jianwen liang Zhongxian Liu Department of Civil Engineering Tianjin University Tianjin 300072 China

This paper investigates in detail the nature of diffraction of plane P waves around a canyon in poroelastic half-space, and studies the effects of incident frequency, drainage condition, porosity, etc, on the diffraction of waves. It is shown that the surface displacement amplitudes of the drained case are close to those of the undrained case, however, the surface displacement amplitudes of the dry case are very different from those of the saturated （either drained or undrained） cases. There are large phase shift between the dry case and the saturated cases, as well as slightly longer resultant wavelengths for the undrained case than those for the drained case and longer resultant wavelengths for the drained case than those for the dry case. For small porosity the surface displacement amplitudes for the saturated cases are almost identical to those for the dry case; while for large porosity, the effect of drainage condition becomes significant, and the surface displacement amplitudes for the undrained case are larger than those for the drained case. As the incident frequency increases, the effect of porosity becomes significant, and more significant for the undrained case than that for the drained case. As the porosity increases, the pore pressures increase significantly but their oscillations become smoother. As the incident frequency increases, the pore pressures become more complicated.

关键词： poroelastic half-space canyon diffraction plane P wave surface displacement pore pressure

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2.5D scattering of incident plane SH waves by a canyon in layered half-space

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Earthquake Science 2010年第1期23卷 25-33页

作者： Zhenning Ba jianwen liang Department of Civil Engineering Tianjin University Tianjin 300072 China

This paper presents 2.5D scattering of incident plane SH waves by a canyon in layered half-space by the indirect boundary element method (IBEM). The free field response is carried out to give the displacements and stresses on the line which forms boundary of the canyon. The fictitious uniform moving loads are applied to the same line to calculate the Green's functions for the displacements and stresses. The amplitudes of the loads are determined by the boundary conditions. The displacements due to the free field and from the fictitious uniform moving loads have to be added to obtain the whole motion. The numerical results are carried out for the cases of a canyon in homogenous and in one layer over bedrock. The results show that the 2.5D wave scattering problem is essentially different from the 2D case, and there exist distinct differences between the wave amplification by a canyon in layered half-space and that in homogeneous half-space. The reasons for the distinct difference are explored, and the effects of the thickness and stiffness of the layer on the amplification are discussed.

关键词： canyon layered half-space plane SH wave amplification 2.5D scattering