摘要:

AbstractThe present paper deals with the buckling and vibration of prismatic beams resting on an elastic half‐space. The computational procedure developed herein utilizes the advantages of both an analytical approach and a finite element scheme. This is accomplished by deriving exact frequency and axial force dependent stiffness matrices using the analytical solutions of the governing differential equation as ‘shape functions’. The major advantages of the proposed approach over previous ones are pointed out and discussed in detail. Numerical results demonstrating the performance of the proposed method are presented in the final part of the

ISSN:0098-8847    

DOI:10.1002/eqe.4290160802

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractA plane strain model for dynamic soil‐structure interaction problems under harmonic state is presented. The boundary element method is used to study the response of a homogeneous isotropic linear elastic soil. The far field displacement at the free surface is approximated by an outgoing Rayleigh wave. The finite element method is used to describe the response of the building, of the foundation and possibly of a finite part of the inhomogeneous non‐linear soil. Two coupling procedures are described. The model is applied to a problem previously studied in the antiplane case. Incident P, SV and Rayleigh waves are considered. The results show an amplification and an attenuation of the structure motion with frequency when incident Rayleigh waves and P, SV body waves are respectively conside

ISSN:0098-8847    

DOI:10.1002/eqe.4290160803

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractThe boundary element method has been successfully applied in the past to the analysis of hydrodynamic forces in two‐ and three‐dimensional finite water reservoirs subjected to seismic ground motions. In extending the method to an infinite reservoir, the loss of energy due to pressure waves moving away towards infinity must be taken into account. In addition, for both finite and infinite reservoirs, energy is lost owing to partial absorption of the waves incident on a flexible bottom consisting of alluvial deposits. This paper presents the results of more recent research on the application of the boundary element method to the analysis of 2D reservoir vibration. Two different formulations are used: a constant boundary element formulation and a linear boundary element formulation. Special boundary conditions to treat infinite radiation and foundation damping have been incorporated in both formulations. Numerical results have been obtained for each of the two alternative formulations and compared against each other as well as with classical solutions and results obtained by other research

ISSN:0098-8847    

DOI:10.1002/eqe.4290160804

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractFour widely used structural system identification methods are presented. Based on Bayesian estimation theory, two new formulae and their derivations are shown. Time domain responses of two frames when subjected to the ground motion of the El Centro earthquake are computed then transformed to the frequency domain. Frequencies and mode shapes of frames are extracted from Fourier spectra. Using these frequencies and mode shapes, a parametric study is conducted, and the system identification methods are compared and discussed. The importance of a prior analytical model on the rate of convergence of the revised parameters is investigated. Recommendations are given regarding the feasibility of each method for more accurate estimation. A model suitable for parameter identification of three‐dimensional frames is presented. This model, with different identification methods, is used to estimate the parameters of a two‐storey fr

ISSN:0098-8847    

DOI:10.1002/eqe.4290160805

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractAmbient response measurements were made on an eighteen‐storey building at three different stages of construction to detect any changes in the frequencies, mode shapes and stiffness with construction. The first nine frequencies and corresponding mode shapes for each stage of construction are found. A comparison is made among these mode shapes and frequencies and with the mode shapes and frequencies of an analytical model incorporating beams, columns, shear walls, panels and diagonal elements. The added effects, on frequencies and mode shapes, of non‐structural elements such as stairs, elevators, claddings and partition walls are studied. Using Improved Statistical Structural Identification, an attempt is made to study the stiffening effect of non‐structural elements by updating the stiffness matrix of the bui

ISSN:0098-8847    

DOI:10.1002/eqe.4290160806

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractAn analysis of the influence of strong motion duration on the response spectra is presented. The analysis is based on the concept of evolutionary power spectral density and first passage estimations for non‐stationary random vibrations. To compare the response for different durations the criteria of constant Arias intensity and constant excitation level have been applied. The paper presents a numerical analysis of the effect of strong motion duration on various response statistics for a linear oscillator. Results indicate a decrease of peak response and first passage probability with increasing strong motion duration for constant Arias intensit

ISSN:0098-8847    

DOI:10.1002/eqe.4290160807

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractThis paper presents a theoretical analysis of the effect of duration on the damage of structures subjected to earthquakes. The earthquake excitation is modelled by a non‐stationary random process whose response spectrum is probabilistically consistent with a design response spectrum specified independently of the duration. Damage is assumed to accumulate with the cyclic application of large strains in the structural members. Two types of structure are examined: one representative of a steel structure and the other reprsentative of a reinforced concrete structure. The level of expected damage is found to be a strong function of both the ductility of the response and the duration of the excitation. Results are presented for systems with linear stiffness and a particular form of softening behaviou

ISSN:0098-8847    

DOI:10.1002/eqe.4290160808

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractOptimum strong‐motion array geometry for source inversion is quantitatively determined for each of three types of earthquake faults: strike—slip, dip‐slip and offshore subduction thrust. The estimation is done by using the source inversion method1,2previously developed and based on Wolberg's prediction analysis.3Only the far‐field S waves are taken into account in source inversion; we test only the ability to estimate seismic moments of subfault elements. A comparison of the optimum array geometries obtained in this study with the ones proposed on the basis of an empirical judgment at the 1978 International Workshop on Strong‐Motion Earthquake Instrument Arrays4shows that the Workshop geometries are not the best ones as far as source studies are concerned. The most preferable array involves two different kinds of stations regardless of the target fault type: stations close to the fault and aligned parallel to its strike, and stations surrounding the fault area with good azimuthal coverage. The former stations resolve the later stage of the rupturing process while the latter stations resolve the earl

ISSN:0098-8847    

DOI:10.1002/eqe.4290160809

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

ISSN:0098-8847    

DOI:10.1002/eqe.4290160810

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

ISSN:0098-8847    

DOI:10.1002/eqe.4290160812

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY