石家庄某小学基坑降水引发地面沉降模拟

Three-dimensional Numerical Simulation of Land Subsidence Caused by Foundation Pit Dewatering

为了准确模拟预测由基坑降水引起的地面沉降问题,以石家庄某小学教学楼基坑为例,运用美国地质调查局开发的三维地下水渗流与地面沉降耦合计算软件Processing MODFLOW建立了基坑地面沉降模型。结果表明在布置16口抽水井并且保持单井抽水量为35 m3/d时,计算15 d后基坑内地下水位降至底板以下0.5 m^1 m,并且基坑外沉降最大值为3.6 mm,满足基坑开挖要求。通过后续施工可以看出,模拟结果与实际情况较为符合,精度较高。

In order to accurately simulate land subsidence caused by foundation pit dewatering, a certain primary school foundation pit in Shijiazhuang was taken as an example. Land subsidence model was established by using three - dimensional groundwater seepage and land subsidence coupling computation software Processing MODFLOW developed by USGS. It shows that when 16 pumping wells are laid out in foundation pit and the pumping quantity of single well is 35 m3/d, groundwater level is down to 0. 5 m - 1 m under base plate of foundation pit and the maxi- mum land subsidence is 3.6 mm outside the foundation pit after calculating for 15 days. This result meets the foun- dation excavation demand.