（吉林建筑大学土木工程学院， 长春 130118）

［摘要］通过原创的小模型半面桩原状土试验，分析不同含水率细粉砂土情况下，混凝土扩盘桩桩周土体的破坏状态。研究结果表明，在竖向荷载作用下，混凝土扩盘桩盘下土体的破坏性状基本为滑移破坏，但滑移范围随含水率变化而不同，其承载力也会受到影响，因此估算混凝土扩盘桩的承载力时应该乘以一个相应的调整系数，含水率不同调整系数也应有所差异。研究中改进了半面桩埋置试验的承土器和埋桩方法，提出了混凝土扩盘桩单桩抗压承载力计算时应考虑含水率，弥补了实际工程中忽略土体含水率对扩盘桩竖向承载力影响的缺陷，为完善混凝土扩盘桩在细粉砂土土层的设计应用提供理论基础。

［关键词］混凝土扩盘桩； 细粉砂土； 含水率； 抗压破坏； 桩周土

中图分类号：TU473-1文献标识码：A文章编号：1002-848X(2020)11-0119-04

Experimental study on influence of water content of fine sand soil for compressive failure of concrete expansion pile

QIAN Yongmei, ZHOU Tingting, TIAN Wei

(College of Civil Engineering, Jilin Jianzhu University, Changchun 130118， China)

Abstract:Through the original small model half-sided pile undisturbed soil test, the failure state of the soil around the pile of concrete expansion pile with different moisture content of fine sand soil was analyzed. The study results show that under the vertical load, the failure behavior of the soil under the concrete expansion pile is basically slip failure, but the slip range varies with the change of water content, and the bearing capacity is also affected. Therefore, the bearing capacity of concrete pile should be estimated by multiplied by a corresponding adjustment coefficient and the different adjustment coefficient of water content should also be different. The soil-bearing device and pile-burying method of half-sided pile-burying test were improved. Water content should be taken into account in the calculation of the compressive bearing capacity of concrete expansion pile, which makes up for the defects of ignoring the influence of soil water content on vertical bearing capacity of expansion pile in practical engineering. It provides a theoretical basis for improving the design and application of concrete expansion pile in fine sand soil layer.

Keywords:concrete expansion pile; fine sand soil; water content; compressive damage; soil around pile

*国家自然科学基金资助项目（51678275）。

作者简介：钱永梅，博士，教授, Email:306109357@qq.com。