土工基础 ›› 2020, Vol. 34 ›› Issue (5): 607-611.

• 专题论述 • 上一篇    下一篇

真空预压处理前后的基桩水平承载力特征值数值试验研究

王 伟1,崔 晓2,金培阳1,汪 立1   

  1. (1. 中国电力工程顾问集团中南电力设计院有限公司,武汉 430071;2.华润电力(仙桃)有限公司,湖北仙桃 433000)
  • 收稿日期:2020-06-24 修回日期:2020-07-01 出版日期:2020-10-20 发布日期:2020-11-02
  • 作者简介:王 伟(1983-),男,高级工程师,注册岩土工程师,一级注册建造师,研究方向为岩土工程勘察,检测等。

Numerical Experimental Study on The Characteristic Value of Horizontal Bearing Capacity of Foundation Pile Before and After Vacuum Preloading

WANG Wei1, CUI Xiao2, JIN Peiyang1, WANG Li1   

  1. (1.Central Southern China Electric Power Design Institute Co. Ltd., China Power Engineering Consulting Group, Wuhan 430071;2.China Resources Electric Power Co. Ltd., Xiantao 433000)
  • Received:2020-06-24 Revised:2020-07-01 Online:2020-10-20 Published:2020-11-02

摘要: 在富水软土地基中,桩基础的水平承载力对确保高耸及大跨距结构的建(构)筑物的稳定性至关重要。对于采用真空预压处理的淤泥质粉质粘土,通过建立三维数值模型,考虑桩土的实际接触关系,计算分析预压处理前后基桩受不同水平力作用下的内力变形及水平承载力特征值的变化规律。计算结果表明:原土体在未处理前,基桩在不同水平推力作用下,桩身受力随入土深度变化趋势基本一样,剪力为0的点约在入土深为2~3 m之间,水平推力越大,桩身受力越大,且水平推力影响深度在0~15 m之间;采用真空预压处理后,考虑不同处理深度时,随着处理深度的增加,基桩水平承载力特征值均增加,但处理深度存在界限值(10 m),当处理深度超过界限值之内,随着处理深度的增加,基桩水平承载力特征值的增加幅度较大;当处理深度超过界限值之后,随着处理深度的增加,基桩水平承载力特征值的增加幅度逐渐减小。因此,在实际运用过程中需要合理确定处理深度。

关键词: 真空预压, 水平承载力, 基桩, 特征值, 数值试验

Abstract: The lateral resistance of the piles in saturated soft soil is important to the stability of tall and large span buildings and other structures. This paper presents three-dimensional numerical analysis results of pile foundations in the vacuum preloading improved mucky silty soft soils. The soil-structure interaction effect was considered in the analysis and the lateral loaded piles in soft soils before and after the preloading were compared. The results indicate that, when a pile in original soft soils under different lateral load, the lateral pile deformation patterns were similar: the point of zero shear is 2~3 meters below the ground. Larger lateral loading results in a larger stress in the pile and the lateral load influence depth is between 0 and 15 meters. When a pile in the vacuum preloading improved soil, with the increase of the soil improvement (limited to 10 meters), the lateral resistance of pile increases with the depth of soil improvement. However, when the soil improvement depth is greater than the limiting depth, the increment of the lateral resistance gradually reduces. Therefore, the improvement depth should be appropriately determined for a cost-effective construction.

Key words: Vacuum Preloading, Lateral Resistance, Foundation Pile, Characteristic Values, Numerical Analysis

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