Stochastic analysis of global traveltime data: mantle heterogeneity and random errors in the ISC data   总被引：1，自引：1，他引：0  

O. Gudmundsson  J. H. Davies  R. W. Clayton 《Geophysical Journal International》1990,102(1):25-43

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Simplified estimation of seismically induced settlements     

E. Vincens  P. Labb  B. Cambou 《国际地质力学数值与分析法杂志》2003,27(8):669-683

This paper proposes a predictive expression of settlements for a dry sand deposit overlying a bedrock and subjected to a seismic motion. The proposed formula combines geometrical and mechanical properties of the soil profile with classical characteristics of the input motion. One of the main concepts developed herein consists in regarding the input motion and the dynamical response as samples of random processes; another key concept consists in the common densification curve from Sawicki. The model introduces a parameter k identified by means of an extensive set of accelerograms. The main advantage of the proposed method consists in allowing fast comparisons of earthquake induced settlements for different soil and motion characteristics and therefore quantifying the damage power of a time‐history input motion. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

Analytical models of the effective permeability of sand-shale reservoirs   总被引：1，自引：0，他引：1  

J. F. McCarthy 《Geophysical Journal International》1991,105(2):513-527

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P-wave coda analysis of short-period array data and the scattering and absorptive properties of the lithosphere   总被引：1，自引：0，他引：1  

Michael Korn 《Geophysical Journal International》1988,93(3):437-449

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Spatial random field simulation by a numerical series representation     

A. Oya  J. Navarro-Moreno  J. C. Ruiz-Molina 《Stochastic Environmental Research and Risk Assessment (SERRA)》2007,21(4):317-326

An approach to the simulation of spatial random fields is proposed. The target random field is specified by its covariance function which need not be homogeneous or Gaussian. The technique provided is based on an approximate Karhunen–Loève expansion of spatial random fields which can be readily realized. Such an approximate representation is obtained from a correction to the Rayleigh–Ritz method based on the dual Riesz basis theory. The resulting numerical projection procedure improves Rayleigh–Ritz algorithm in the approximation of second-order random fields. Simulations are developed to illustrate the convergence and accuracy of the method presented.

J. C. Ruiz-MolinaEmail:

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A fuzzy–random analysis model for seismic performance of framed structures incorporating structural and non‐structural damage     

Xiaoming Gu  Yong Lu 《地震工程与结构动力学》2005,34(10):1305-1321

Past earthquake experiences indicate that most buildings designed in accordance with modern seismic design codes could survive moderate‐to‐strong earthquakes; however, the financial loss due to repairing cost and the subsequent business interruption can be unacceptable. Designing building structures to meet desired performance targets has become a clear direction in future seismic design practice. As a matter of fact, the performance of buildings is affected by structural as well as non‐structural components, and involves numerous uncertainties. Therefore, appropriate probabilistic approach taking into account structural and non‐structural damages is required. This paper presents a fuzzy–random model for the performance reliability analysis of RC framed structures considering both structural and non‐structural damages. The limit state for each performance level is defined as an interval of inter‐storey drift ratios concerning, respectively, the non‐structural and structural damage with a membership function, while the relative importance of the two aspects is reflected through the use of an appropriate cost function. To illustrate the methodology, herein the non‐structural damage is represented by infill masonry walls. The probabilistic drift limits for RC components and masonry walls from the associated studies are employed to facilitate the demonstration of the proposed model in an example case study. The results are compared with those obtained using classical reliability model based on single‐threshold performance definition. The proposed model provides a good basis for incorporating different aspects into the performance assessment of a building system. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

Conditional components for simulation of vector random fields     

J. A.?Vargas-GuzmánEmail author 《Stochastic Environmental Research and Risk Assessment (SERRA)》2003,17(4):260-271

Conditional component random fields (CC) based on Cholesky decomposition of the multivariate spectra are introduced in this study to develop a new method for conditional simulation of vector attributes in environmental and geological phenomena. The CC are independent random fields with covariance models obtained from projections and conditioning in the frequency domain. The approach is to simulate one attribute in the physical space and use the results to estimate the other attributes in the frequency domain. Then, a CC for the next attribute is simulated and projected on the other attributes. In general, any attribute is built as the sum of inverse Fourier transform of the orthogonal projection of previous simulated CC plus a last CC simulated in the physical space. This simulation approach continues in this fashion for several attributes and the order of them may be changed for different realizations. This method allows for data conditioning and simulation. A simplified version for intrinsically correlated random fields allows for an approach that avoids the frequency domain.  相似文献   

大跨度空间网格结构多维多点随机地震反应分析   总被引：4，自引：0，他引：4  

李忠献  林伟  丁阳 《地震工程与工程振动》2006,26(1):56-63

本文建立了三维正交地震动多点激励下大跨度空间网格结构的随机地震反应分析方法,依据现行抗震设计规范的有关规定,确定了平稳随机地震动功率谱密度的模型参数。数值仿真分析了一柱距80m的正方形平板网架分别在一维地震动或三维地震动的一致激励、行波激励和考虑部分相干效应的随机激励下的地震反应。结果表明:考虑地震动的空间效应会很大程度地改变结构杆件的内力,其中控制杆件的内力增幅达到30%;地震动的行波效应对结构杆件内力的影响比随机地震动的部分相干效应的影响更大;三维地震作用比一维地震作用下结构杆件的内力大。由此得出结论,对于大跨度空间网格结构,必须进行多维多点地震激励下的随机地震反应分析。  相似文献   

基于物理的随机地震动模型研究   总被引：15，自引：0，他引：15  

李杰  艾晓秋 《地震工程与工程振动》2006,26(5):21-26

基于物理联系研究地震动随机性,建立了随机地震动与基底输入傅氏谱、场地固有圆频率和场地等价阻尼比之间的物理关系,从随机傅氏谱函数角度描述了地震动随机过程的随机性本质。结合Ⅳ类工程场地的实测地震动记录资料,由数值方法识别了给出基本随机变量的概率分布参数。与实测记录对比表明,本文建立的随机地震动模型具有明确的物理概念,可充分反映地震动的变异性特征。  相似文献   

钢筋混凝土框架结构体系抗震可靠度及其抗力衰减影响分析   总被引：1，自引：0，他引：1  

侯爽  欧进萍 《地震工程与工程振动》2006,26(5):114-119

结构体系可靠度分析面临的主要问题是失效模式多,但通过pushover分析方法在一定情况下可以得到结构的最弱失效模式。本文将结构体系抗力等效为与结构特定损伤状况相关的结构的顶点位移,结构的地震作用效应由pushover分析及能力谱法求得。考虑结构体系抗力随机性的主要影响因素以及地震作用的随机性,分别求得了结构抗力及地震作用效应的概率分布参数,通过一次二阶矩方法求得了结构体系可靠度,并进一步研究了结构层数变化及耐久性退化因素对结构体系可靠度的影响。研究发现,结构体系的抗震可靠度水平随着结构层数的增加有减小的趋势,结构体系的抗震可靠度水平随着结构使用期增加而降低,降低幅度与薄弱层个数有关,薄弱层越多,降低幅度越大。  相似文献