摘要
以厦门市地铁莲花路口站深基坑施工为例,采用FLAC 3D数值模拟软件建立三维分析模型,对不同工况下基坑施工引起的坑外地表沉降影响及规律进行了分析。结果表明:降水井深度越深、间距越大,地表沉降值越小;随着止水帷幕深度的增加,抑制地表沉降的效果越明显,但当超过一定深度后,抑制效果减弱,止水帷幕渗透系数大小对地表远处沉降的影响不大;回灌施工对地表沉降控制的影响不大,回灌井数量和回灌比不宜过大。综合沉降控制效果和工程成本,认为当抽水井井深为24 m、间距为10 m,止水帷幕渗透系数为10-9 cm/s、深度为28 m时对地表沉降控制效果最好。
With the construction of the deep foundation pit of the Lianhuakou Subway Station of Xiamen Metro as an example,the FLAC 3-D numerical simulation software is used in the paper to establish a three-dimensional analysis model to analyze the influence and law of the surface settlement beyond the pit caused by the construction of the foundation pit under different working conditions.The results show that the deeper the dewatering well is and the larger the spacing is,the smaller the surface settlement value will be.With the increase in the depth of the water-stopping curtain goes up,the surface settlement is more and more obviously restrained,however,when the depth is beyond a certain value,the inhibition effect is weakened,and the seepage coefficient of the water-stopping curtain has little effect on the remote settlement of the surface.The influence of the reinjection construction on the surface settlement control is not great,and the number of reinjection wells and the reinjection ratio should not be too large.Upon the basis of comprehensively considering both the effect of settlement control and the engineering cost,it is found that,when the depth of the pumping well is 24 m,the spacing is 10 m,the seepage coefficient of the water-stopping curtain is 10-9 cm/s and the depth of the water-stopping curtain is 28 m,the effect of the surface settlement control is the best.
作者
包溪娟
BAO Xijuan(The 1st Engineering Co.Ltd.of the 18th Bureau Group of China Railway,Zhuozhou 072750,China)
出处
《国防交通工程与技术》
2021年第2期54-57,共4页
Traffic Engineering and Technology for National Defence
关键词
地铁车站
深基坑
降水井
止水帷幕
回灌
地表沉降控制
subway station
deep foundation pit
dewatering well
water-stopping curtain
reinjection
surface settlement control
