剪切速率对结构性吹填软土力学特性影响试验研究

杨爱武; 雷博

doi:10.13544/j.cnki.jeg.2015.01.002

剪切速率对结构性吹填软土力学特性影响试验研究

doi: 10.13544/j.cnki.jeg.2015.01.002

杨爱武^1,2,
雷博^1,2

1.
天津城建大学土木工程学院天津 300384;
2.
天津市软土特性与工程环境重点实验室天津 300384

基金项目:

国家自然科学基金(41372291)资助

详细信息

作者简介:
杨爱武(1971-),男,博士,教授,主要从事软土地基处理及土体微结构研究. Email: tulilab@163.com

中图分类号: TU41
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- 被引次数: 0
出版历程
- 收稿日期: 2014-01-15
- 修回日期: 2014-07-17
- 刊出日期: 2015-02-25

EXPERIMENTAL STUDY ON EFFECT OF SHEARING RATE ON MECHANICAL BEHAVIOR OF STRUCTURED SOFT DREDGER FILL

YANG Aiwu^1,2,
LEI Bo^1,2

1.
School of Civil Engineering, Tianjin Chengjian University, Tianjin 300384;
2.
Key Laboratory of Tianjin Soft Soil Character and Engineering Environment, Tianjin 300384

摘要

摘要: 黏土在剪切变形过程中,剪切速率的不同会对其结构破坏产生不同影响,从而影响其力学特性.本文以天津滨海新区吹填软土为研究对象,在对吹填软土关于结构性讨论的基础上,开展了剪切速率对其力学性状影响的三轴试验研究,分析其剪切速率力学效应.试验结果表明:随着剪切速率的提高,在低围压条件下,吹填软土的强度及其结构屈服应力均先减小后增大,存在临界剪切速率,而在高围压条件下,强度及其结构屈服应力则逐渐增大,与剪切速率呈正相关关系,临界剪切速率逐渐消失; 吹填软土的黏聚力在不同围压下随剪切速率提高均呈现减小趋势,内摩擦角在低围压条件下随剪切速率提高呈现增大趋势,在高围压条件下则随剪切速率提高呈现减小趋势; 在剪切过程中,孔隙水压力均随着轴向应变的增大到某一值然后稳定下来,随着围压的进一步加大,孔隙水压力的稳定值会随剪切速率的提高呈减小趋势.
- 吹填软土 /
- 结构性 /
- 剪切速率 /
- 力学特性 /
- 结构屈服应力
Abstract: In clay shear deformation process, different shear rates have different effects on its structural damage, thus affecting its mechanical behavior. This paper takes the soft dredger fill from Tianjin Binhai New Area as research object. It discusses the structural about soft dredger fill, and carries out the triaxial shear tests to study effects on mechanical behavior caused by different shear rates, analyzes its mechanical effect of shearing rate. The test result indicates that as the shear rate increases, at low confining pressure condition, the strength and structural yield stress of soft dredger fill increase at first and then decrease, existing a critical shear rate. At high confining pressure condition, the strength and structural yield stress increase gradually, which shows a positive correlation with the shearing rate. The critical rate is disappearing gradually. However, at different confining pressure conditions, the cohesion of dredger fill decreases as the shearing rate increases. As the shearing rate increases, the internal friction angle shows an increasing trend at low confining pressure condition, which shows a decreasing trend at high confining pressure condition. In the shearing process, pore water pressure increases with the increase of axial strain to a certain value, and then becomes stable. With further increase of confining pressure, the stable value of pore water pressure shows a decreasing trend with the increase of shearing rate.
- Soft dredger fill /
- Structural /
- Shearing rate /
- Mechanical behavior /
- Structural yield stress

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参考文献(1)

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