厚软场地的地震动特征及设计反应谱研究

Study on Seismic Effects and the Design Spectra of a Site with Deep and Soft Soil Layers

根据场地土层静、动力性能参数的原位测试和动三轴试验结果,进行厚软场地土层地震反应分析,研究厚软场地的地震动效应及地震动特性,并结合工程实例讨论了对应不同地震设防水平(50年超越概率63%、10%和3%)厚软场地的设计反应谱,分析了现行规范设计反应谱应用的局限性,成果对相关工程也有借鉴作用。

In this paper, a specific project site which has deep overburden and soft soil layers is considered. According to the in situ results of soil layer dynamic parameters and dynamic tri-axial test, the seismic effects and seismic response characteristics of the site are discussed based on earthquake response analysis of soil layers. Comparing the caculated acceleration spectra of different earthquake levels (with exceedance probabilities of 63%, 10% and 3% respectively in 50 years) with the Aseismic Design Code (JTT004-89), the limitation of existing design spectrum of the existing code is analyzed. It is not safe to use the code spectrum for project aseismic design of the site. The results are of practical use, and can be used for reference in other similar projects.