含剧烈地震动作用不同埋深砂土液化判别统一公式  

An unified formula for predicting sand liquefaction in different buried depths under severe seismic ground motion

作　　者：袁晓铭[1] 费扬 陈龙伟[1] 袁近远 陈同之 张思宇 王义德 YUAN Xiaoming;FEI Yang;CHEN Longwei;YUAN Jinyuan;CHEN Tongzhi;ZHANG Siyu;WANG Yide(Key Laboratory of Earthquake Engineering and Engineering Vibration of China Earthquake Administration,Institute of Engineering Mechanics,China Earthquake Administration,Harbin,Heilongjiang 150080,China;Hangzhou Architectural Design and Research Institute Co.,Ltd,Hangzhou,Zhejiang 310008,China)

机构地区：[1]中国地震局工程力学研究所中国地震局地震工程与工程振动重点实验室,黑龙江哈尔滨150080 [2]杭州市建筑设计研究院有限公司,浙江杭州310008

出　　处：《岩石力学与工程学报》2021年第10期2101-2112,共12页Chinese Journal of Rock Mechanics and Engineering

基　　金：中国地震局工程力学研究所基本科研业务费专项资助项目(2018A01);黑龙江省科学基金资助项目(ZD2019E009)。

摘　　要：震害调查和工程实践均表明,发展含剧烈地震动作用及深埋砂层下合理的液化判别方法为现代城市和重大工程抗震设防所必须。收集整理近期大地震液化新数据,剖析现有代表性液化判别方法,提出基于标准贯入试验的砂土液化判别统一模型和公式,以适于含剧烈地震动作用下不同埋深砂层的液化判别。所提出的双曲线型液化判别模型,对不同深度砂层具有一致的统一表达,符合液化临界线基本特征,且能够做到深、浅砂层和高、低地震动强度作用同时兼顾,较我国规范现有模型明显合理,较国际上基于CSR理论、沿深度分四段表达的NCEER模型明显先进。新公式通过了PGA<0.9 g作用下液化砂层埋深30 m内大量实测液化数据的检验,克服了我国规范砂层埋深超过10 m时严重保守的弊端,弥补了我国规范PGA>0.4 g和砂层埋深20 m以下液化判别方法的空白,也消除了国际上NCEER方法中砂层埋深超过10 m后液化临界线出现回弯的不合理现象以及很强和剧烈地震动(0.25 g<PGA<0.9 g)作用下较为保守的缺点。提出的公式已被具有样板规范性质的《建筑工程抗震性态设计通则》修订版采纳,可为相关规范修订及工程应用提供指导与技术支持。The earthquake investigation and the engineering practice both show that it is necessary to develop reasonable liquefaction prediction methods in deep buried sand layers under the actions containing severe seismic ground motion for modern cities and major projects.Based on the survey on the recent liquefaction events and the analysis for the existing representative liquefaction prediction methods,a SPT-based unified discriminant model and the corresponding formula are proposed suitable for sand layers of different buried depths under the action containing the severe seismic ground motion.The proposed hyperbolic model has a consistent and unified expression for sand layers of different depths and conforms to the basic characteristics of the liquefaction critical line.The proposed model can adapt to the situations of shallow and deep sand layers as well as high and low seismic intensities and hence,is more reasonable than the existing models in China’s codes and more advanced than the international CSR theory-based NCEER models with four sections along the depth.The new formula is approved by a large number of measured liquefaction data within sand layers of 30 m buried depth under PGA<0.9 g,which overcomes the serious conservative disadvantages in the buried depth range of 10–20 m in China’s codes and makes up for the vacancy of the discriminant methods for PGA>0.4 g and the sand layers below 20 m in China’s codes.The new formula also eliminates the unreasonable phenomenon of NCEER method that the critical boundary of liquefaction turns back when the buried depth of sand layers exceeds 10 m and overcomes the relatively conservative shortage of NCEER method under very strong and severe ground motion of 0.25 g<PGA<0.9 g.The proposed formula has been adopted in the revised version of the General Rule for Performance-based Seismic Design of Buildings with role model and can provide guidance and technical support for related specification revision and engineering application.

关 键 词：岩土工程 液化判别 深度一致模型 剧烈地震动作用 双曲线模型 建筑工程抗震性态设计通则 

分 类 号：TU43[建筑科学—岩土工程]