Scaling of design earthquake ground motions for tall buildings based on drift and input energy demands

Seismic response spectra are amongst one of the most important tools for characterizing earthquake ground motions. In design practice, the response spectra are presented without including any load history, hence the nonlinear analysis of structures based solely on conventional earthquake response spectra is theoretically unsound, particularly for long-period or vertically irregular high-rise buildings. In this paper, a concept of seismic damage evolution is introduced and the method of analysis for characterizing the process of seismic damage to structures under earthquakes is presented. Seismic damage evolution spectra for analysis and design of high-rise buildings are then developed as an effective means of describing and simplifying earthquake ground motions. These spectra are shown to be very useful in selecting the ground motion-time history and, particularly, validating the equivalent static-load analysis and design of high-rise buildings under near-fault pulse-like ground motions. Case studies of the seismic inelastic performance of two vertically irregular, tall buildings are presented considering the seismic damage evolution spectra.

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Variation of Earthquake Ground Motions with Focus on Site Amplification Factors: A Case Study

Engineering, Technology & Applied Science Research ◽

10.48084/etasr.2856 ◽

2019 ◽

Vol 9 (4) ◽

pp. 4355-4360 ◽

Cited By ~ 2

Author(s):

Y. Fukushima ◽

T. Nagao

Keyword(s):

Hazard Analysis ◽

Probability Distributions ◽

Ground Motions ◽

Strong Motion ◽

Site Amplification ◽

Group Delay Time ◽

Amplification Factors ◽

Earthquake Ground Motions ◽

Design Earthquake

In this paper, an evaluation of the variation of earthquake ground motions with a focus on site amplification factors based on spectral analysis is presented. By using strong motion record obtained at six sites in Japan, probability distributions of site amplification factors were shown. The relations between standard deviations of site amplification factors and distances between the sites were studied. The variations of representative values of earthquake ground motions based on the variations of site amplification factors were discussed by using probabilistic seismic hazard analysis with focus on Fourier amplitude and group delay time. The distributions of peak ground accelerations and peak ground velocities were shown. It is suggested that design earthquake ground motions considering the average site amplification factors may lead the engineering design on the dangerous side.

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Selection of the Test Specimens for Seismic Tests of Air-Operated Valve Actuators for Nuclear Power Plants

Volume 8: Seismic Engineering ◽

10.1115/pvp2019-93168 ◽

2019 ◽

Author(s):

Nobuo Kojima ◽

Yoshitaka Tsutsumi ◽

Yoshinao Matsubara ◽

Koji Nishino ◽

Yasuyuki Ito ◽

...

Keyword(s):

Nuclear Power ◽

Power Plants ◽

Nuclear Power Plants ◽

Ground Motions ◽

Test Results ◽

Earthquake Ground Motions ◽

Dynamic Function ◽

Design Earthquake ◽

Seismic Tests ◽

Selection Of

Abstract The soundness for the function of air-operated valves in nuclear power plants during earthquake has been investigated via seismic test results and so forth. Since the seismic response acceleration has increased more and more with a recent reassessment of design earthquake ground motions conducted according to the revised Japanese nuclear safety regulation, it is necessary to evaluate the soundness for the function of various valves subject to large acceleration beyond design basis. The air-operated valves currently installed in the nuclear power plants in Japan play the important roles in the sever accident events. In this study, we classified them based on the valve type, manufactures and the previous test results. Furthermore, we proposed the strategy for evaluating the seismic-proof and the seismic test condition for examining the soundness of the dynamic function. Here, the dynamic function is defined as the function required under and after earthquakes.

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