英语翻译

英语翻译
Abstract:Previous papers have reported on the performance of a recently developed nonlinear ground response analysis code,SPECTRA,
with reference to the prediction of the free-field response at a Large-Scale Seismic Test site in Lotung,* during the M6.5
earthquake of May 20,1986.Two more major earthquakes of different characteristics shook this test site later that same year,a M6.2
earthquake that occurred on July 30 and a M7.0 earthquake that occurred on November 15.The present article analyzes the free-field
responses recorded by a downhole array from these latter two events using the code SPECTRA and a widely used equivalent linear
analysis code SHAKE.The studies focus on the relative accuracy and sensitivity of the two codes with respect to the variations of the input
material parameters,using time histories,acceleration response spectra,Fourier acceleration amplitude spectra,and Arias intensities as
criteria for the comparison.The two codes captured the general wave form of the acceleration histories well,but there was a general
tendency for both codes particularly SHAKE!to underpredict the Arias intensities of the earthquakes.
DOI:10.1061/~ASCE!1090-0241~2002!128:54!
CE Database keywords:Stress analysis; Bounding surface; Finite element method; Ground motion; Plasticity