软土地区超长单桩承载特性的现场试验研究

张骞; 李术才; 张乾青; 李利平; 周宗青

软土地区超长单桩承载特性的现场试验研究 English Version

1. 山东大学岩土与结构工程研究中心,山东济南 250061; 2. 中国矿业大学深部岩土力学与地下工程国家重点实验室, 江苏徐州 221116

基金项目: 中国矿业大学深部岩土力学与地下工程国家重点实验室开放基金项目（SKLGDUEK1210）

详细信息

作者简介:
张骞(1986- )，男，山东潍坊人，博士研究生，主要从事基础工程和隧道工程的研究工作。E-mail: bowanghou1@sina.com。

中图分类号: TU473.1
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出版历程
- 收稿日期: 2013-06-14
- 发布日期: 2013-11-24

Bearing behaviors of super-long single pile in soft soil areas

1. Research Center of Geotechnical and Structural Engineering, Shandong University, Jinan 250061, China; 2. State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining & Technology, Xuzhou 221116, China

摘要

摘要: 软土地区超长钻孔灌注桩现场静载试验表明,浆液上返作用对桩侧泥皮的固化作用和桩端浆液对桩端沉渣和持力层的压密固化作用使得后注浆桩的承载能力得以提高。使用荷载下,桩身压缩占桩顶沉降的90%以上,最大试验荷载时桩顶沉降的70%来自桩身压缩。在对超长桩进行设计时,不能忽视桩身压缩对桩顶沉降的影响。超长桩侧上部土层摩阻力具有不同程度的软化现象,而中下部土层侧摩阻力未完全发挥。传统的超长桩承载力计算方法和其实际承载能力会有一定误差。
- 钻孔灌注桩 /
- 注浆 /
- 桩身轴力 /
- 桩土相对位移 /
- 桩侧摩阻力
Abstract: The static load test results of super-long bored piles in soft soil areas show that the curing effect of slurry on mud cake around pile shaft and the compaction and curing effect of slurry on the sediment and bearing layer can improve the bearing capacity of single pile. Under the working load, the compression of pile shaft accounts for more than 90% of pile top settlement, and the percentage of super-long pile top settlement caused by the compression of pile shaft is over 70% under the maximum load. Therefore, the influence of pile shaft compression on the pile head settlement should not be ignored in the design of super-long piles. Moreover, it can be concluded that the skin friction softening occurs in the upper soil layers of the super-long piles, whereas the skin friction in the deeper soil layers can not be fully mobilized. The traditional methods for the bearing capacity calculation of supper-long piles will have a certain error in the actual bearing capacity.
- bored pile /
- grouting /
- axial force /
- relative displacement of pile-soil /
- skin friction

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参考文献(8)

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