中文摘要：

为了了解9度设防区场地的动力特征,应用脉动法对四川省西昌市（9度设防）25处典型场地进行了脉动测试,并采用Nakamura方法对实测数据进行了处理,获得了该地区场地卓越周期的分布规律以及地基处理、断裂带、湖泊对场地动力特性的影响,为反应谱理论在9度设防区的应用提供了试验依据。测试结果表明：西昌市场地的卓越周期主要分布在0.60s以上;采用换填法的地基处理方式不能明显改善场地的动力特性;安宁河断裂带两岸场地的卓越周期随与河道距离的增大而减小;邛海沿岸场地的卓越周期随与岸边距离的增大而增大。

英文摘要：

In order to study the dynamic properties of sites in the areas with seismic fortification intensity 9,the typical sites in Xichang,Sichuan Province（with seismic fortification intensity 9） are measured based on the site microtremor measurement.The distribution of predominant periods of sites and the impact of ground treatment,river and lake on the sites,are acquired according to the data processing with Nakamura method,and it provides the test basis for response spectrum theory to be used in the areas with seismic fortification intensity 9.Based on the test results,it is clear that the predominant periods of sites are almost lager than 0.60 s.Ground treatment can not improve the dynamic performance of site obviously.The predominant periods of sites become lager with the distance increasing from the riverbed.The predominant periods of sites decrease with the distance increasing from the side of the lake.