摘要:

AbstractIn this paper, soil‐structure interaction studies are presented for buildings which collapsed at the Tofas automobile factory, Bursa, Turkey, during the 28 March 1970 Gediz earthquake. Acceleration response spectrum curves of the ground were determined using the vibrations of an after shock recorded by a Willmore velocity seismometer. These spectrum curves provide an essential source of information for establishing the reasons of collapse, as well as for explaining the relative response to the earthquake of various buildings in the factory area.The factory not only is 135 km away from the epicentre, but also is far outside the fifth degree damage intensity zone. The prime reason why a low value of ground acceleration caused such surprisingly heavy damage to modern reinforced concrete structures is concluded to be the resonance phenomenon arising from the natural period of the structures coinciding with the predominant period of the soi

ISSN:0098-8847    

DOI:10.1002/eqe.4290010302

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractThe simplest form of input required for step‐by‐step simulation of response of a structure to a gusty wind is a stochastic process having Gaussian distribution and a specified power spectrum. Methods for generating such a process are described in detail, and the extension outlined for generating a number of partially correlated input processes having specified power spectra and cross‐sp

ISSN:0098-8847    

DOI:10.1002/eqe.4290010303

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractKolkewadi Dam, a masonry gravity dam in India, is under construction at a'site which was considered to be non‐seismic at the time of planning and design. Subsequently, some major and minor earthquake shocks have occurred in the area. In view of the earthquake activity in the region, it was necessary to estimate the seismic resistance of the dam. A dynamic analysis of the two highest monoliths of the dam has been carried out, based on the probable ground motion expected at the site, including a simplified analysis, treating the dam as a cantilever beam and a detailed analysis considering two‐dimensional behaviour by the finite element method. It is concluded that the dam will be able to safely withstand the severest shock that has occurred in the region. The behaviour of models of one monolith has also been studied experimentally using a shake table. The experimental behaviour of the models compares favourably with the behaviour obtained theoretically, indicating the applicability of the theoretical method of analy

ISSN:0098-8847    

DOI:10.1002/eqe.4290010304

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractA general step‐by‐step solution technique is presented for the evaluation of the dynamic response of structural systems with physical and geometrical nonlinearities. The algorithm is stable for all time increments and in the analysis of linear systems introduces a predictable amount of error for a specified time step. Guidelines are given for the selection of the time step size for different types of dynamic loadings. The method can be applied to the static and dynamic analysis of both discrete structural systems and continuous solids idealized as an assemblage of finite elements. Results of several nonlinear analyses are presented and compared with results obtained by other methods and from experime

ISSN:0098-8847    

DOI:10.1002/eqe.4290010305

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractThree‐dimensional models of a subaqueous tunnel were built on a shaking table and vibrated for the purpose of investigating the dynamic behaviour of the tunnel. The material of the soft surface layer was gelatin gel and that of the tunnel was silicon rubber.In addition, earthquake observations at the site of the real subaqueous tunnel have been carried out using accelerometers and strain gauges set on the walls of the tunnel. At the site, micro‐tremors were also measured.In these studies, it was noted that non‐uniform displacements of the ground along the tunnel axis were caused by variations of the dynamic behaviour of the ground, and that the tunnel deforms correspondingly to the varying deformations of the ground.From these experimental results, a mathematical model of the subaqueous tunnel was formulated for anti‐seismic design

ISSN:0098-8847    

DOI:10.1002/eqe.4290010306

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractThe two‐dimensional scattering and diffraction of plane SH waves by a semi‐cylindrical canyon is analysed for a general angle of wave incidence. The closed‐form solution of the problem shows that the surface topography can have prominent effects on incident waves only when the wavelengths of incident motion are short compared to the radius of a canyon. The surface amplification of displacement amplitudes around and in the canyon changes rapidly from one point to another, but the amplification is always less than 2. The over‐all trends of amplification pattern are determined by two principal parameters: (1) γ, the angle of incidence of plane SH waves, and (2) η, the ratio of radius of the canyon to one‐half wave length of incident waves. The higher η leads to greater complexity of the pattern of surface displacement amplitudes characterized by more abrupt changes of amplification from one point to another, while γ mainly determines the over‐all trends of displacement amplitudes. For grazing and nearly grazing incidences, for example, a strong shadow zone is developed behind the canyon.The qualitative analysis of the topographic effects on the Pacoima Dam accelerogram,1based on the semi‐cylindrical canyon, suggests that this strong‐motion record was not seriously affected by surface topography of

ISSN:0098-8847    

DOI:10.1002/eqe.4290010307

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractA systematic procedure is presented for the stability and accuracy analysis of direct integration methods in structural dynamics. Amplitude decay and period elongation are used as the basic parameters in order to compare various integration methods. The specific methods studied are the Newmark generalized acceleration scheme, the Houbolt method and the Wilson θ‐method. The advantages of each of these methods are discussed. In addition, it is shown how the direct integration of the equations of motion is related to the mode superposition analys

ISSN:0098-8847    

DOI:10.1002/eqe.4290010308

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractLiquefaction of saturated sand deposits under seismic excitation is studied on the basis of a fatigue failure approach. The model includes a stochastic treatment of the input, of the soil response and of the cumulative pore pressure effects produced by cycling stresses in the soil. A method of establishing safety factors against liquefaction is also considered. Results obtained from analysis of a case history confirm the applicability of the model for engineering purposes.

ISSN:0098-8847    

DOI:10.1002/eqe.4290010309

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

ISSN:0098-8847    

DOI:10.1002/eqe.4290010310

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

ISSN:0098-8847    

DOI:10.1002/eqe.4290010301

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY