双层承压水层赋存特征对深基坑施工变形的影响  

Influence of Double-Layer Pressurized Water Layer Characteristics on Deformation of Deep Foundation Pit Construction

作　　者：何同继 HE Tongji(China Railway 16th Bureau Group Co.Ltd.,Beijing 100018,China)

机构地区：[1]中铁十六局集团有限公司,北京100018

出　　处：《铁道建筑技术》2025年第3期170-175,共6页Railway Construction Technology

基　　金：中铁十六局集团有限公司科技研发计划项目(K2021-19C)。

摘　　要：承压水层对基坑施工稳定性影响大,多层承压水层所带来的风险更大。据此,通过正交试验法分析了双层承压水层赋存特征对基坑施工变形的影响,并结合现场监测数据进行了验证。结果表明,基坑变形的主要影响因素为层1顶埋深和层2厚度。数值模拟显示,基坑开挖及降水过程中,地连墙的挠度受承压水层影响显著,特别是第二承压水层对变形增量的贡献较大,最大挠度可达16 mm。监测数据还表明,施工活动、周围建筑物及地表荷载等因素对挠度变化有重要影响。第一承压水层附近的挠度最大,而第二承压水层减压效应使地连墙初期出现轻微挠度,后期挠度显著增大,最大值可达8 mm,表明地连墙施工对第二承压水层的影响极为显著。Pressurized water layer has a significant impact on structures in foundation pit construction,and the risk posed by multiple layers of confined aquifers is even greater.Accordingly,the influence of double-layer pressurized water layer on the deformation of foundation pit construction was analyzed by orthogonal test method and verified with on-site monitoring data.The results show that the main influencing factors of foundation pit deformation are the top burial depth of layer 1 and the thickness of layer 2.Numerical simulation shows that the deflection of the diaphragm wall is significantly affected by the pressurized water layer during the excavation and precipitation process of the foundation pit,especially the second pressurized water layer contributes more to the deformation increment,and the maximum deflection can be up to 16 mm.The monitoring data also show that the construction activities,the surrounding buildings,and the surface loading and other factors have an important effect on the change of the deflection.The deflection near the first pressurized water layer is the largest,while the decompression effect of the second pressurized water layer causes slight deflection of the diaphragm wall at the initial stage,and then the deflection increases significantly at the later stage,with a maximum value up to 8 mm,which indicates that the construction of the diaphragm wall has a very significant effect on the second pressurized water layer.

关 键 词：地铁基坑 双层承压水层 正交试验 施工变形 现场监测 

分 类 号：TU753[建筑科学—建筑技术科学] U231.3[交通运输工程—道路与铁道工程]