摘要:

AbstractThe coupled lateral‐vertical‐rocking dynamic response of spring‐viscous damper isolated structures is considered. The force‐displacement relation of the viscous dampers is described by an experimentally calibrated fractional derivative viscoelasticity model. The equations of motion are derived and reduced to a form for direct solution by the discrete Fourier transform method. The validity and accuracy of the derived solution are demonstrated by comparison with shake table test results.The developed analysis procedure is employed in the seismic analysis of a recently constructed isolated structure. The analytical and experimental results demonstrate that spring‐viscous damper isolation systems are capable of providing both effective seismic and vibration

ISSN:0098-8847    

DOI:10.1002/eqe.4290210801

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractBased on a reliability level 2 method, a procedure is proposed to design reinforced concrete structures for elevated tanks subjected to seismic action, with a specified probability of failure in a 50‐year design life.To evaluate the probability of failure the ultimate limit state is obtained when the top column displacement demanded by the earthquake, a random variable, reaches the allowable displacement, which is here treated as deterministic.The seismic action is characterized probabilistically by the power spectral density function of the ground acceleration, which is obtained from a design spectrum. The strength and ductility of an annular column section of confined reinforced concrete for cyclic loads are evaluated with design aids.Design charts are made for a given tank capacity and specified seismic zone that allow one to choose different combinations of strength, stiffness and ductility for the same tolerable probability of failure. A step by step method is suggested for the design of the annular column section, choosing finally the most convenient design. The advantage of this methodology is shown through a numerical exampl

ISSN:0098-8847    

DOI:10.1002/eqe.4290210802

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractArray observation is an efficient tool to investigate various characteristics of earthquake ground motion. However, seismographs used in arrays may involve unexpected errors in their orientations. Methods of orientation error estimation were developed in three‐dimensional space by comparing recorded ground motions at a reference point with those at a checking point. A maximum cross‐correlation method and a maximum coherence method were proposed and their accuracy was demonstrated. The earthquake ground motions recorded in the Chiba array and in two other arrays were used in numerical examples. Non‐trivial orientation errors were detected for all these arrays. The cross‐correlation coefficients and the coherence values between two points increased significantly by correcting the estimated orientation

ISSN:0098-8847    

DOI:10.1002/eqe.4290210803

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractThis paper presents a method of identification for determining non‐linear dynamic models for certain hysteretic structures. Particular attention is given to modelling and identifying the hysteretic behaviour of structures from strong‐motion earthquake data. In this method, the response is separated into mode‐like components which are analogous to those of a linear system. Based on modelling of the generalized restoring force of each mode‐like component, both non‐hysteretic and hysteretic non‐linear models are incorporated into the general methodology. A non‐hysteretic model provides an initial estimate for a final hysteretic model. The approach is applicable even when data are available from only a small number of locations in the structure. The structural model identified from this method provides a means to predict the response to future events and, ultimately, to examine the damage to a structure as a result of

ISSN:0098-8847    

DOI:10.1002/eqe.4290210804

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractA new response spectrum method is developed for seismic analysis of linear multi‐degree‐of‐freedom, multiply supported structures subjected to spatially varying ground motions. Variations of the ground motion due to wave passage, loss of coherency with distance and variation of local soil conditions are included. The method is based on fundamental principles of random vibration theory and properly accounts for the effects of correlation between the support motions as well as between the modes of vibration of the stru

ISSN:0098-8847    

DOI:10.1002/eqe.4290210805

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

ISSN:0098-8847    

DOI:10.1002/eqe.4290210806

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY