实际硬场地下现有等效线性化分析程序的对比

The comparison of existing Equivalent linear analysis program under actual stiff site based on Ki K-net array

SHAKE2000和LSSRLI-1是目前国内外应用最为广泛的两种等效线性化土层地震反应分析程序。本文以Ki K-net台阵中28个硬场地(一、二类场地)、基底输入峰值在12gal-370gal间的56个实测记录为基础,取三种土动模量和阻尼比非线性工况,对这两种程序进行对比检验,结果表明:土体弱非线性时二者计算出的峰值加速度误差绝大多数可以忽略,而土体为均值和强非线性时误差大多数可以忽略;二者与实测结果差异均只有少数可忽略,但SHAKE2000计算结果要好于LSSRLI-1;LSSRLI-1与实测反应谱存在较大差异和显著差异的几率要大于SHAKE2000,对土为强非线性情况尤为如此;二者计算出的土层剪应变多数情况相差小于20%,但LSSRLI-1计算出的剪应变普遍大于SHAKE2000,且个别工况下差异显著。

SHAKE2000 and LSSRLI-1 are currently the two most widely used equivalent linear seismic response of soil analysis programs at home and abroad. These two programs were tested by three kinds of nonlinear dynamic modulus and damping ratio of soil conditions,based on 56 measured records,which PGA was from12 gal to 370 gal,selected from 28 stiff sites( site classⅠ and siteclassⅡ) of the Ki K-net stations. The results show that: the error of peak acceleration calculated by the two programs vastlycan be ignored for the weakly nonlinear soil. The errors mostly can be ignored for the soil of moderateand strongly nonlinear of dynamic property. The difference between the calculated and the measured results only few can be ignored. But the results of SHAKE2000 are better than that of LSSRLI-1. Compared with SHAKE2000,the probability of existing a large difference of responsespectrabetween calculated by LSSRLI-1 and the measured is great,especially for the strongly nonlinear soil. The shear strain of soil calculated by the two programs mostly differ less than 20%,but the shear strain of soil calculated by LSSRLI-1generally is larger than by SHAKE2000,and the difference is obvious forindividual conditions.