砂砾土振动体变评价方法与离心机模型试验验证  

Evaluation method for shaking-induced volumetric strain for gravelly soils and validation by centrifuge model tests

作　　者：夏鹏[1,2] 周燕国 刘凯[1,3] 陈云敏[1] XIA Peng;ZHOU Yanguo;LIU Kai;CHEN Yunmin(MOE Key Laboratory of Soft Soil and Geoenvironmental Engineering,Institute of Geotechnical Engineering,Center for Hypergravity Experiment and Interdisciplinary Research,Zhejiang University,Hangzhou 310058,China;Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering,Hohai University,Nanjing 210024,China;China State Construction Silkroad Construction Investment Group Co.,LTD,Xi'an 710000,China)

机构地区：[1]浙江大学软弱土与环境土工教育部重点实验室,浙江大学岩土工程研究所,浙江大学超重力研究中心,浙江杭州310058 [2]河海大学岩土力学与堤坝工程教育部重点实验室,江苏南京210024 [3]中建丝路建设投资有限公司,陕西西安710000

出　　处：《岩土工程学报》2024年第S01期207-211,共5页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(51988101,52278374,52308347);高等学校学科创新引智计划项目(111计划,B18047)。

摘　　要：2008汶川地震出现了砂砾土大范围液化致灾现象,现场震害调查表明砂砾土场地存在砾石效应影响,现有砂土场地的震后沉降评价方法不适用于砂砾土场地。对此,在“张-社本”振动体变评价方法的基础上进一步发展了考虑砾石含量的砂砾土振动体变评价方法,然后开展动三轴试验确定评价方法中的相关参数,最后开展3组典型砾石含量的砂砾土地基离心机振动台模型试验对评价方法的可靠性进行验证。试验结果表明,砾石含量越高,振动引起的场地沉降变形越小;砂砾土振动体变评价方法可以较为准确地预测新近沉积砂砾土场地的震后沉降,但对存在地震历史影响的砂砾土场地,本文提出的评价方法较为保守,建议进一步发展考虑地震历史效应的砂砾土振动体变评价方法。Liquefactions of gravelly soils are widely distributed in the 2008 Wenchuan earthquake.Field investigations show that the existing settlement evaluation methods for sands are not applicable to the gravelly soils due to the gravel content effects.It is aimed to develop the evaluation method for shaking-induced volumetric strain for the gravelly soils with consideration of gravel content,which is based on the so-called"Zhang-Shamoto"model.The dynamic triaxial tests are conducted to parameterize the evaluation method,and three centrifuge model tests on the gravelly soil grounds with typical gravel contents are carried out to check the performance of the proposed evaluation method.The test results show that the higher the gravel content,the smaller the shaking-induced settlement.The proposed evaluation method can accurately predict the shaking-induced settlement for recently deposited gravelly soils,but shows a conservative prediction performance in cases with pre-shaking effects,which suggests the need to further improve the proposed evaluation method by considering the pre-shaking effects.

关 键 词：砂砾土 动三轴试验 振动体变 沉降 离心机振动台 模型试验 

分 类 号：TU432[建筑科学—岩土工程]