长江科学院院报 ›› 2015, Vol. 32 ›› Issue (9): 99-103.DOI: 10.11988/ckyyb.20140206

• 岩土工程 • 上一篇    下一篇

基于极限分析法的基坑支护入土深度研究

李和志1,赵永清2,陈春鸣3   

  1. 1.江西科技学院 南昌市材料研究与结构检测重点实验室,南昌 330098;
    2.湖南科技学院土木工程与建设管理系,湖南 永州 425199;
    3.东莞理工学院城市学院 城市与环境科学系,广东 东莞 523419
  • 收稿日期:2014-03-21 出版日期:2015-09-20 发布日期:2015-09-10
  • 作者简介:李和志(1985-),男,湖南双峰人,工程师,硕士,主要从事边坡工程及地基基础研究与教学方面的工作,(电话)15083828091(电子信箱)lihezhi3301@qq.com。
  • 基金资助:
    江西省科技计划项目(20123BBG70180);江西科技学院规划建设学科项目(结构工程);江西科技学院自然科学研究项目(ZR14YB08)

Depth of Driven Excavations in Foundation Pit Based on Limit Analysis Method

LI He-zhi1,ZHAO Yong-qing2,CHEN Chun-ming3   

  1. 1. Nanchang Key Laboratory of Material and Structure Detection, Jiangxi University of Technology, Nanchang 330098, China;
    2. Department of Civil Engineering and Construction Management, Hunan University of Science and Engineering, Yongzhou 425199, China;
    3. Department of City and Environmental Science, City College of Dongguan University of Technology, Dongguan 523419, China
  • Received:2014-03-21 Online:2015-09-20 Published:2015-09-10

摘要: 基于极限分析上限法,分析了基坑底部刚塑性三角形楔体ABC,BDE和对数螺旋线受剪区BCD 3个区域的速度场,建立了基坑底部塑性区的虚功率方程,据此推导出基坑抗隆起稳定安全性要求下的支护入土深度上限解和支护入土深度为t时的基坑抗隆起稳定性安全系数k。经工程实例验证可知,基坑支护入土深度上限解和抗隆起稳定性安全系数计算式合理,可为将来同类型的基坑支护入土深度计算提供参考和经验,并可进一步完善和提高基坑底部土体稳定的准确率。

关键词: 基坑支护, 入土深度, 极限分析法, 上限解, 安全系数

Abstract: According to upper bound theorem of the limit analysis method, we analyzed the velocity field at the bottom of active slip zone ABC and transition zone BCD and passive slip zone BDE in a foundation pit. Virtual work-rate equation of plastic area at the bottom of the foundation pit was established. On this basis, the upper-bound solution to the depth of support excavations which meets the requirement of stability against upheaval was induced, and the stability safety factor k was solved when the support depth t was given. Engineering examples verified that the upper-bound solution and the formula of stability safety factor k are rational. The results could provide reference for the calculation of support depth in similar foundation pits, and improve the correctness of bottom soil stability in foundation pit.

Key words: excavation support, support depth, limit analysis method, upper-bound solution, safety factor

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