洞庭湖地区某特大桥饱和砂土液化判别及其液化特征

在地震作用下,洞庭湖地区存在的大量砂土层会出现液化破坏。通过SPT（现场标准贯入试验）、SWVT（剪切波速测试）和CPT（静力触探试验）等原位技术对洞庭湖地区某特大桥饱和砂土层进行了地震液化判别并对其液化特征进行分析。结果表明,综合采用静力触探和标准贯入试验进行液化判别的方法结果较好,静力触探方法更适合本地区砂土液化评判;在本特大桥,液化等级随着砂土顶板埋深的减小而由不液化变为严重的趋势,液化指数随砂土顶板埋深的减小而增大,基本呈线性关系;当埋深超过13.3 m时,基本不会产生液化,而当埋深小于5.95 m时液化等级为严重可能性大。

Prediction and characteristics of sand liquefaction for a highway in the region of Dongting Lake

Sand liquefaction hazards may occur in the Dong Ting Lake region for the great deal of sandy soil.The results of Sand liquefaction prediction are proposed by methods of standard penetration test（SPT）,cone penetration test（CPT） and shear wave velocity test（SWVT）,and characteristics of sand liquefaction are analysis.It has been shown that synthetically using the methods of SPT and CPT is suitable for estimating the liquefaction,and the method of CPT is more suitable.In the Dong Ting Lake region,with decreasing of the embedded depth of sandy soil,the index of liquefaction is increased,and the liquefaction grade is more severity.Liquefaction mainly occurred in the sandy soil with embedded depth less than 13.3 m,and the liquefaction grade is severity with embedded depth less than 5.95 m.