隔水帷幕对深基坑降水开挖变形控制的影响

依托杭州沿江大道地下综合管廊深基坑工程，土体采用HSS模型进行有限元数值模拟，分析基坑降水开挖下基坑及邻近管线的变形，模拟结果与监测结果吻合较好，验证了有限元计算模型和参数选取的合理性。基于模拟提出隔断式基坑降水优化方案，并研究稳态渗流下隔水帷幕插入深度不同时基坑及邻近管线的变形响应。结果表明：随着悬挂式隔水帷幕深度加深，坑内外水头差线性增大，围护结构侧移峰值线性增大，管线竖向位移、坑外地表沉降线性减小；相较于悬挂式隔水帷幕，隔断式隔水帷幕对控制基坑降水引起的坑外地表沉降及邻近管线变形均有着显著优势，但对于围护结构变形控制则不利。

Influence of waterproof curtain on deformation control of deep foundation pit dewatering and excavation

Based on the deep foundation pit project of the utility tunnel of Yanjiang Avenue in Hangzhou, the HSS model was used for finite element numerical simulation to analyze the deformation of the foundation pit and adjacent pipelines under the dewatering excavation of the foundation pit. The simulation results are in good agreement with the monitoring results, which verifies the rationality of the finite element calculation and parameter selection. Based on the results, an optimized plan for dewatering of the partitioned foundation pit has been proposed, and the deformation response of the foundation pit and adjacent pipelines was studied when the penetration depth of the water-insulating curtain was different under steady-state seepage. The research results show that as the depth of the suspended waterproof curtain increases, the head difference of ground water between the inside and outside of the pit and the peak value of the lateral displacement of the retaining structure increases linearly, and the vertical displacement of the pipeline and the surface settlement outside the pit decrease linearly; Compared with the suspended waterproof curtain, the waterproof curtain has significant advantages in controlling the surface settlement outside the pit and the deformation of adjacent pipelines, however it is more unfavorable for the deformation control of the retaining structure.