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51.
This paper presents an analytical solution for the lateral dynamic response of a pipe pile in a saturated soil layer. The wave propagations in the saturated soil and the pipe pile are simulated by Biot's three‐dimensional poroelastic theory and one‐dimensional elastic theory, respectively. The governing equations of soil are solved directly without introducing potential functions. The displacement response and dynamic impedances of the pipe pile are obtained based on the continuous conditions between the pipe pile and both the outer and inner soil. A comparison with an existing solution is performed to verify the proposed solution. Selected numerical results for the lateral dynamic responses and impedances of the pipe pile are presented to reveal the lateral vibration characteristics of the pile‐soil system. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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This article presents a method for the nonlinear analysis of laterally loaded rigid piles in cohesive soil. The method considers the force and the moment equilibrium to derive the system equations for a rigid pile under a lateral eccentric load. The system equations are then solved using an iteration scheme to obtain the response of the pile. The method considers the nonlinear variation of the ultimate lateral soil resistance with depth and uses a new closed‐form expression proposed in this article to determine the lateral bearing factor. The method also considers the horizontal shear resistance at the pile base, and a bilinear relationship between the shear resistance and the displacement is used. For simplicity, the modulus of horizontal subgrade reaction is assumed to be constant with depth, which is applicable to piles in overconsolidated clay. The nonlinearity of the modulus of horizontal subgrade reaction with pile displacement at ground surface is also considered. The validity of the developed method is demonstrated by comparing its results with those of 3D finite element analysis. The applications of the developed method to analyze five field test piles also show good agreement between the predictions and the experimental results. The developed method offers an alternative approach for simple and effective analysis of laterally loaded rigid piles in cohesive soil. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Long-period surface waves and mantle boundary undulations 总被引:2,自引:0,他引:2
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Transmission fluctuations across an array and heterogeneities in the crust and upper mantle 总被引:1,自引:0,他引:1
Adopting the spectral approach, we derive the formulation of angular coherence and transverse coherence of transmission fluctuations. Our derivation and results provide new insight on transmission fluctuation analysis. A review of research work on fluctuation analysis using observations at large seismic arrays such as LASA and NORSAR-follows. We point out that the model of a single-layer Gaussian medium cannot explain the angular coherence of NORSAR data and a more general model of a non-Gaussian, multi-scale, vertically inhomogeneous random media is needed. The model of a two-layer power-law medium proposed by Flatté and Wu is among the simplest of such models. 相似文献
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常德市水文地质及电测深、电测井的资料反映了孔隙水含水层涌水量的大小与含水层厚度、颗粒组分及其结构的多因素的复杂组合──—厚度(M)与视电阻率(ρ_s)的乘积密切相关,据此可预测单井涌水量。 相似文献