Studies on Seismic Safety of Structure-Soil Interaction System and Its Rational Design Procedures

结构-土相互作用系统抗震安全性及其合理设计方法研究

• 批准号: 01044094
• 负责人: TAKEMIYA Hirokazu
• 金额: $ 3.84万
• 依托单位: Okayama University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for international Scientific Research
• 财政年份: 1989
• 资助国家: 日本
• 起止时间: 1989 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01044094/
• 关键词: Site topography; Wave propagation; Equivalent linearization; Pile-soil system; Dynamic soil-structure Interaction; Soil nonlinearity; Nonlinear soil structure interaction; 2-dimensional model

This study aims at getting useful information for design of extended large scale civil engineering structures through the analysis of such structures with emphasis on dynamic soil structure interaction. The following issues has been focused :(1) Wave propagation in the soil deposit with the local topography(2) Dynamic soil-structure interaction and the foundation impedance and the effective input motion(3) Nonlinear soil effect in strong earthquake motion on structural response(4) Progressive input motion to multiple input structuresTopographical study of the construction site is made to investigate the seismic wave amplification in 2 dimensional sense. The frequency domain analysis, the time domain analysis and their hybrid approach have been employed. The parameter used are the incident wave types, angle of incidence, topography, aspect ratio between wide and depth of the soil deposits. Analysis is conducted for representative nondimensional frequency as defined by the surface width … More of the deposit and the incident wave length. Soil amplification due to the local topography depends significantly on the wave type and noodimension frequency.The Green function involved for the BEM analysis is developed for the concentrated as well as uniform distributed forces. The Fourier transform method needs the wave number integration for the inverse transform. This is performed by the Gauss quadrature and by the modified Clenshaw-Curtis method. The Green function for multilayer makes it possible to perform the soil deposits with layered half space. Detail discussion is made for the offset of source forces in the indirect boundary element method. The time domain analysis used the Cgniad-de Hoop method for the analytical solution for a full plane.Group pile foundations are constructed on soft soils to support superstructures. The present analysis took deliberate consideration for the pile-soil-pile interaction. The substructure method is used to advantage, splitting the soil and piles. The soil analysis is performed by use of the thin layer method. The pile analysis is made from the mass discrete system and the mass distributed system. The investigation is focused the pile head impedance function. The simulation is carried out for a single pile loading test.The investigation for rigid buried foundations is also executed with interest to soil layering, the interaction between adjacent foundation through soil, fillback effect.Soils in strong ground motion attain high strains, indicating heavily nonlinear behavior with drift of the base line for the nonperiodic seismic input. Assuming certain stress-strain relationship, response computation are made for the 1-dimensional and the 2-dimensional models by the direct step-by-step integration scheme and by the equivalent method based on effective stain. The results are compared for the time histories and the response spectra. The difference of modeling and the characteristic of nonlinearity are clarified. The importance of the 2-dimensional modeling is emphasized in order to interpret the recorded data.Pile supported structural response with nonlinear soil properties is investigated, together with the equivalent linear analysis. Soil-deformation is based on the assumed soil stress-strain characteristic. Although the equivalent linearization technique predicts reasonably the truly nonlinear response, the difference between these responses becomes appreciable as the input motion grows. Especially, such nonlinear structural response gives rise to reduced acceleration but amplified displacement. Less

本文旨在通过对大型土木工程结构的动力相互作用分析，为此类结构的设计提供有益的信息。（1）局部地形条件下波在存款土层中的传播;（2）土-结构动力相互作用、基础阻抗和有效输入运动;（3）强震运动中土的非线性效应对结构反应的影响;（4）多输入结构的渐进输入运动。采用了频域分析、时域分析以及频域和时域混合分析的方法。所使用的参数是入射波类型、入射角、地形、土壤沉积物的宽度和深度之间的纵横比。对由表面宽度定义的代表性无量纲频率进行分析 ...更多信息 存款和入射波长。由于局部地形而产生的土壤放大作用在很大程度上取决于波的类型和无维频率。边界元分析所涉及的绿色函数是针对集中力和均匀分布力而开发的。傅里叶变换方法需要波数积分进行逆变换。这是由高斯求积和修改的克伦肖-柯蒂斯方法。多层的绿色函数使得可以进行分层半空间的土壤沉积。对间接边界元法中的源力偏移问题进行了详细的讨论。时域分析采用Cgniad-de Hoop法求解全平面的解析解。本分析考虑了桩-土-桩的相互作用。采用子结构法，将土和桩分开。土壤分析采用薄层法。从质量离散系统和质量分布系统两个方面对桩进行了分析。研究的重点是桩顶阻抗函数。对单桩荷载试验进行了数值模拟，对刚性基础进行了研究，考虑了土层分层、相邻基础之间的相互作用、回填效应等问题，在强地震动作用下，地基土的应变达到很高，表现出严重的非线性特性，在非周期地震动作用下，地基土的基线发生了偏移。假定一定的应力应变关系，采用直接逐步积分法和基于有效应变的等效法对一维和二维模型进行了响应计算。结果进行了比较的时程和反应谱。阐明了两种建模方法的区别和非线性的特点。为了解释记录数据，强调了二维模型的重要性，研究了非线性土特性对桩承结构响应的影响，并进行了等效线性分析。土体变形是基于假定的土体应力-应变特性。虽然等效线性化技术合理地预测了真正的非线性响应，但随着输入运动的增加，这些响应之间的差异变得明显。特别是，这种非线性的结构响应引起的加速度减小，但放大的位移。少

项目成果

H. Takemiya: "Computational Methods for Seismic Response Analysis" Proceedings of the 3rd China Earthquake Engineering Conference. 1. 1-22 (1990)

H.竹宫：《地震响应分析计算方法》第三届中国地震工程学术会议论文集。

H. Takemiya: "Hybrid Analysis for Topographical Site Response and Its Characteristics" Proceedings of the 8th Japan Earthquake Engineering Symposium. 2. 325-330 (1990)

H. Takemiya：“地形场地响应及其特征的混合分析”第八届日本地震工程研讨会论文集。

竹宮 宏和: "Computational Methods for Seismic Response Analyes" 中国第3回地震工学会議. No.1. 1-22 (1990)

竹宫宏和：“地震反应分析的计算方法”，第三届中国地震工程学会第1-22期（1990）。