摘要
钢支撑的架设时机,既需要满足基坑支护受力和变形的要求,也要为支撑架设和土体开挖预留空间。基于工程实践的实际需求,选择西安典型黄土场地的深基坑为研究对象,从钢支撑轴力、围护桩桩体水平变形和弯矩分布等三个指标出发,在现场监测的基础上,对比分析了两种支撑架设时机、四个开挖留置宽度条件下,围护桩-支撑-土体之间的相互作用。研究表明:两种支撑架设时机条件下,钢支撑轴力、围护桩桩体水平向变形和弯矩分布均有小幅度增长,增幅在10%~15%以内,基坑开挖实施过程中,整体受力变形风险可控;随着钢支撑端头位置处开挖留置宽度的减小,钢支撑架设的滞后效应越来越显著,围护桩桩体的水平向变形及弯矩均有所增长;选择合理的留置宽度,是保障支撑架设时机优化的关键。
The erection time of steel support should not only meet the requirements of stress and deformation of foundation pit support,but also reserve space for support erection and soil excavation.Based on the actual needs of engineering practice,this paper selects the deep foundation pit of typical loess site in Xi’an as the research object,then compares and analyzes the interaction between retaining pile,support and soil under the conditions of two kinds of support erection time and four excavation retaining widths.The results are as follows.Under the conditions of two kinds of support erection time,the axial force of steel support,the horizontal deformation of retaining pile and the distribution of bending moment increase slightly,with an increase of less than 10%~15%,and during the implementation of foundation pit excavation,the overall stress and deformation risk is controllable;With the decrease of excavation retaining width at the end of steel support,the lag effect of steel support erection is more and more significant,and the horizontal deformation and bending moment of retaining pile are increased;Choosing a reasonable retaining width is the key to ensure the optimization of support erection time.
作者
何秋敏
亢佳伟
常渭涛
邓国华
HE Qiumin;KANG Jiawei;CHANG Weitao;DENG Guohua(Xi’an Loess Underground Project Technology Consulting Co.,Ltd.,Xi’an,Shaanxi 710000,China;Xi’an University of Technology,Xi’an,Shaanxi 710048,China)
出处
《水利与建筑工程学报》
2022年第3期53-60,共8页
Journal of Water Resources and Architectural Engineering
基金
国家自然科学基金项目(52178355)
陕西省自然科学基础研究计划资助项目(2022JM-216)。
关键词
基坑工程
钢支撑架设
土体变形
钢支撑轴力
foundation pit engineering
steel support erection
soil deformation
axial force of steel support
作者简介
何秋敏(1978-),女,工程师,主要从事基坑支护方面的设计和研究工作。E-mail:251519879@qq.com。
