摘要
砂土液化是地震地质较为常见的一种现象,常会引起一些工程病害,对其准确评价和预测较为困难,常采用原位测试方法进行液化评估。以赤壁长江公路大桥场地液化判别为例,在分析国内规范法和国外Seed简化法的基础上,分别利用剪切波测试方法及标准贯入试验结果进行了砂土液化判别,并对判定结果的可靠性进行了评估。通过研究得出结论:《岩土工程勘察规范》与《建筑抗震设计规范》的判别深度较浅,在20 m范围内,且对利用标贯击数判别砂土液化,峰值加速度为0.20 g时前者偏于保守;相对于规范法,Seed简化方法提供了各种原位测试的计算公式,且可对深部的砂层液化提供进一步的判别,判别结果可作为规范法的补充;多种原位测试方法的综合比较和分析有利于提高对砂土液化的判别准确性。
Although the sandy soil liquefaction under a seismic event is one of the major hazards in the geotechnical engineering,the soil liquefaction evaluation and prediction of the potential are difficult,and the in-situ testing evaluation methods are usually used.This paper presents various sandy soil seismic liquefaction evaluation methods by using in-situ testing methods.Earthquake damage of sands liquefaction is one of the most serious engineering disasters in geotechnical engineering.In situ test methods are often used to evaluate liquefaction because of the liquefaction evaluation and prediction is difficulty.Relying on the Chibi Yangtze River Highway Bridge Project,we analysis the domestic code methods and Seed simplified methods,and the engineering characteristics of each sands,then liquefaction evaluation of each sand layer is carried out by using shear wave test and standard penetration test respectively.The research results show that:the discrimination depth of"code for Investigation of Geotechnical Engineering"and"Code For Seismic Design Of Building"is relatively shallow,within the range of 20 m,and the former is conservative for the use of SPT blow to discriminate sands liquefaction;compared with the code methods,seed simplified methods provide various calculation formulas,and can provide further discrimination for deep sands liquefaction,the discrimination results can be used as a supplement to the cod methods;the comprehensive comparison and analysis of various in-situ testing methods are helpful to improve the accuracy of sand liquefaction identification.
作者
高清材
张国超
GAO Qingcai;ZHANG Guochao(China Railway Major Bridge Reconnaissance&Design Institute Co.Ltd.,Wuhan 430050)
出处
《土工基础》
2021年第2期222-227,共6页
Soil Engineering and Foundation
关键词
剪切波测试
标准贯入试验
砂土液化
规范法
Seed简化法
shear waves velocity
standard penetration test
liquefaction of sandy soils
code methods
seed simplified methods
