考虑软岩剪胀效应的嵌岩桩荷载传递机理分析

赵明华; 夏润炎; 尹平保; 杨超炜; 徐卓君

doi:10.11779/CJGE201406003

考虑软岩剪胀效应的嵌岩桩荷载传递机理分析 English Version

湖南大学岩土工程研究所,湖南长沙 410082

基金项目: 国家自然科学基金项目（51278187）

详细信息

作者简介:
赵明华(1956- ),男,湖南洞口人,教授,博士生导师,主要从事桩基础及软土地基处理等研究。E-mail: mhzhaohd@21cn.com。

中图分类号: TU473.1
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出版历程
- 收稿日期: 2013-08-17
- 发布日期: 2014-06-19

Load transfer mechanism of socketed piles considering shear dilation effects of soft rock

Institute of Geotechnical Engineering, Hunan University, Changsha 410082, China

摘要

摘要: 嵌岩桩在竖向荷载作用下,桩-岩结构面剪胀效应对侧阻力的发挥过程具有重要影响。首先,根据软岩中嵌岩桩桩-岩结构面的一种非平面剪切破坏模式,利用滑移线场法求解了发生剪切破坏时的荷载值及剪切位移值,建立了桩-岩结构面剪切函数,并通过现有的室内模型试验验证了该剪切函数的合理性。其次,基于桩-岩结构面剪切函数,建立了考虑软岩剪胀效应的嵌岩段桩身荷载传递方程,导得了嵌岩桩桩身荷载传递表达式。在此基础上,进一步分析探讨了桩-岩结构面粗糙度、岩石力学性质及桩-岩结构面法向刚度等因素对塑性阶段侧阻力分布的影响。最后以某实际工程为例,计算得到了桩身荷载传递曲线,并将其与实测曲线进行对比发现计算曲线与实测曲线吻合较好,验证了计算方法的适用性。
- 桩基础 /
- 嵌岩桩 /
- 软岩 /
- 荷载传递 /
- 剪胀效应
Abstract: For the socketed piles under vertical load, pile-rock joint shear dilation effect has a great influence on side friction. This issue is based on a nonplanar failure model of pile-rock joint. Firstly, the value of shear force is solved when asperity fails by means of the slip-line field theory, and the corresponding shear displacement is obtained. A shear function is established based on the shear dilation mechanism, and the comparison with the experimental results shows a good correspondence. Secondly, based on the derived shear function, the load transfer equations for the pile are established considering the dilation effects, and the expression for load transfer of the pile is deduced. Furthermore, the effect of several parameters on plastic shear force is analyzed, such as joint roughness and rock strength and normal stiffness. Finally, a project is taken as an example, and the load transfer curve of the pile is calculated and compared with the measured one. The results are in good agreement with the measured data, which verifies the availability of the proposed method.
- pile foundation /
- socketed pile /
- soft rock /
- load transfer /
- shear dilation effect

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参考文献(20)

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