沿海某机场扩建工程基坑监测分析

基于机场禁飞区改建工程基坑围护结构及周围土体变形监测结果,结合软土基坑的变形规律,对复杂施工环境和施工时间限制条件下的围护墙体变形、坑后土体竖向位移、支撑轴力以及立柱桩隆沉等变化规律的时间和空间效应做了总结。研究表明:围护结构测斜沿深度呈现出先增大后减小的趋势,水位平移最大值位置出现在开挖面附近,且围护结构水平位移具有明显的时空效应;地表沉降出现沉降槽,深层土体开挖引起地表沉降为总沉降的主要部分,底板浇筑有效地抑制了墙后地表沉降;支撑轴力随施工进度而增加,第2道支撑的施加可减少第1道支撑轴力;立柱桩位移为上浮,其大小随着基坑开挖而增大并趋于稳定。研究结果对机场禁飞区改建工程基坑开挖具有一定参考价值。

Foundation pit monitoring of an coastal airport expansion project

Based on mounts of monitoring data from airport no fly zone expansion project foundation pit, the supporting structure deformation, ground settlement, axial force and pile displacement under complex construction environment and limited construction time were comprehensive analyzed. The results showed that: the horizontal displacement of retaining wall was slight at upper and lower ends, but broad in the middle, increases with the excavation and has a space-time effect. The surface settlement has settlement trough, the subsidence cause by excavation of deep soil is the main part of the total settlement, and the pouring of bottom plate inhibit the surface subsidence effectively. The axial force increases with the construction, and the construction of the second support reduces the axial force of the first support. The displacement of the soldier piles is upward, increases with the excavation and tends to be stable. This study can be a reference for the excavation of foundation pit at airport no fly zone.