基坑不同间距开挖对邻近建筑物影响的研究

Study on the influence of excavation with different spacing on adjacent buildings

摘要

为了探究基坑不同间距开挖对邻近建筑物变形影响规律，以珠海某深基坑施工为工程背景，采用数值分析方法，对比不同基坑与隧道间距下，分析基坑开挖对邻近建筑物变形及受力的影响。结果表明：(1)基坑与隧道不同间距时，邻近建筑物的整体变形随距离的增大而减小，且不同间距相同开挖步时，邻近建筑物水平位移差距不大，砖混住宅的剪力值在150 kN以上，弯矩值在170 kN·m以上，桩基础大厦随基坑的持续开挖，弯矩呈现一定增长；(2)随基坑的持续开挖，不同间距下，隧道无论水平位移还是竖向位移，都随基坑的开挖逐渐增大，其结构受力整体随隧道与基坑的间距的增大而逐渐减小，无论是最大拉应力还是最大压应力，均未超出允许值，结构处于安全状态。

Abstract

In order to study the influence of excavation with different spacing on the deformation of adjacent buildings, a deep foundation pit in Zhuhai is taken as an engineering background, the influence of foundation pit excavation on deformation and stress of adjacent buildings is analyzed. The result show that:(1) the overall deformation of the adjacent buildings decreases with the increase of the distance between the excavation pit and the tunnel at different spacing, and the horizontal displacement of the adjacent buildings has little difference at the same excavation step at different spacing; The shear force value and bending moment value of brick-concrete residence are above 150 kN and 170 kN·m, and the bending moment of pile foundation building increases with the continuous excavation of foundation pit, the horizontal displacement and vertical displacement of the tunnel increase with the excavation of the foundation pit, and the structural stress of the tunnel decreases with the increase of the distance between the tunnel and the foundation pit, the allowed values are not exceeded and the structure is in a safe state.

关键词

基坑开挖 / 邻近建筑物 / 隧道变形 / 数值分析 / 不同间距

Key words

foundation pit excavation / adjacent buildings / tunnel deformation / numerical analysis / different spacing

基金资助

国家自然科学基金重点项目(51939011)

江汉平原高速公路改扩建工程软土路基沉降控制关键技术研究(KJFZ-2019-032-001)