循环荷载下软黏土强度弱化研究及其动力计算应用

王元战; 杨攀博; 孙熙平; 刘翰琪; 胡珅榕

doi:10.11779/CJGE201505007

循环荷载下软黏土强度弱化研究及其动力计算应用 English Version

1. 天津大学水利工程仿真与安全重点试验室,高新船舶与深海开发装备协同创新中心,天津 300072; 2. 中交第一航务工程勘察设计院有限公司,天津 300222; 3. 交通运输部天津水运工程科学研究院,天津 300456

基金项目: 国家自然科学基金项目（51279128）; 国家自然科学基金创新研究群体科学基金项目（51321065）; 交通运输部建设科技项目（2013328224070）

详细信息

作者简介:
王元战(1958- ),男,天津人,教授,博士生导师,从事港口海岸与近海结构设计理论和方法、土与结构相互作用、结构振动分析理论和方法等方面的研究工作。E-mail: yzwang@tju.edu.cn。

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出版历程
- 收稿日期: 2014-07-07
- 发布日期: 2015-05-19

Strength weakening of soft clay under cyclic loading and its dynamic calculation

1. National Key Laboratory of Water Conservancy Engineering Simulation and Security, Coll Aborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Tianjin University, Tianjin 300072, China; 2. CCCC First Harbor Engineering Design Institute Co., Ltd., Tianjin 300222, China; 3. Tianjin Research Institute for Transport Engineering, Tianjin 300456, China

摘要

摘要: 滨海软黏土在波浪循环荷载作用下会发生强度弱化,从而降低软黏土地基承载力,影响结构稳定性。以烟台港原状淤泥质粉质黏土为研究对象,通过室内动三轴试验,以围压、初始静偏应力、循环动应力和循环次数为试验变量,分析不同应力组合作用下的淤泥质粉质黏土的孔压发展规律和不排水抗剪强度弱化规律。根据孔压发展规律拟合出软黏土双曲孔压计算模型,同时利用等效超固结比理论,将得到的孔压模型和强度规律结合起来,提出了综合考虑围压、静偏应力、动应力和循环次数适用于整个动态循环过程的不排水抗剪强度弱化公式,并通过试验对公式进行了验证。最后将公式应用于烟台港防波堤数值模型的动力计算中。从试验到数模,比较完整地提出了一套便于应用于工程实践的考虑地基土体循环弱化效应的动力计算方法。
- 软黏土 /
- 循环荷载 /
- 孔隙水压力 /
- 强度弱化 /
- 数值模型 /
- 动力计算
Abstract: Strength reduction may take place for the littoral soft clay under the action of wave loading. As a result, the bearing capability of soft clay foundation will become significantly lower, and the stabilization of the structures will be affected. By performing cyclic triaxial tests on muddy-silty clay taken from Yantai littoral zone, variation of pore water pressure and weakening of undrained shear strength of clay subjected to different confining pressures, deviator stresses, dynamic stresses and cycle numbers are studied. According to the laws of the development of pore pressure, a model for calculating pore pressure is proposed. In addition, by using the theory of quasi-overconsolidation and combining the pore pressure model and the laws of undrained shear strength, a formula for strength weakening which contains confining pressures, deviator stresses, dynamic stresses and cycle numbers is put forward. The relevant experiment is done to verify the formula. Then it is applied to the dynamic numerical model of a breakwater in Yantai Port. From the experiment to the numerical model, a dynamic calculation method considering the effect of strength weakening which is convenient to be used in engineering is proposed completely.
- soft clay /
- cyclic loading /
- pore water pressure /
- strength weakening /
- numerical model /
- dynamic calculation

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参考文献(13)

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