土工基础

›› 2015, Vol. 29 ›› Issue (3): 161-165.

• 工程实录 • 上一篇    下一篇

典型海相软土动强度-应变特性试验研究

程宇慧1，侯宏伟2   

  1. （1.浙江大港桥梁科学研究有限公司，杭州 310000；2.浙江省建筑科学设计研究院有限公司，杭州 310000）
  • 收稿日期:2015-03-16 出版日期:2015-06-20 发布日期:2015-06-26
  • 作者简介:程宇慧（1981-），女，工程师，主要研究方向为混凝土结构、岩土工程设计及检测。

Test study on Dynamic Strength and Strain Behavior of representative Marine Soil

CHENG Yuhui1,HOU Hongwei2   

  1. (1.Zhejiang Dagang Bridge Research Co. Ltd., Hangzhou, 310000； 2.Zhejiang Academy of Building Research & Design Co. Ltd., Hangzhou 310000)
  • Received:2015-03-16 Online:2015-06-20 Published:2015-06-26

摘要： 以舟山原状海相软土为研究对象，分析循环荷载作用下舟山海相软土动应力、动应变和动孔压随循环荷载次数变化规律以及动强度和动变形特性。试验结果表明：舟山海相软土的动强度随动荷载循环次数的增加而降低；土体动强度指标根据施加动荷载的大小和循环次数而定；应力-应变关系曲线表现为不完全封闭的滞回圈；循环加载下拉、压应变的量级受动应力幅值的影响，土体最后表现为受压破坏；双幅应变随循环次数变化趋势同累计塑性应变发展趋势相同，采用修正的Monismith模型拟合取得比较好的效果。

关键词: 海相软土, 动强度, 动变形, Monismith模型

Abstract: This paper presents test results of stressstrain properties of the undisturbed Zhoushan marine soft cohesive soils under cyclic dynamic loadings. Laboratory tests were focused on the dynamic stresses, strains and pore pressures in relation with the loading cycles. The results indicate that, the dynamic strength decrease with the increase of load cycles and the strength indices are correlated with the magnitude and cycles of dynamic loadings. The stressstrain relationship can be characterized with an incomplete closed hysteresis loop. Under cyclic loading conditions, the magnitude of both tensile and compressive strains are affected by the intensity of the dynamic stress. The failure mode of samples under the dynamic loading is compressive failure. The magnitude of tensile and compressive strains tend to similar with the increase of loading cycles and the development of plastic strains. The development of the dynamic strain can be characterized by the modified Monismith model.  

Key words: Marine Soft Cohesive Soils, Dynamic Strength, Dynamic Deformation, Monismith Model