复杂环境下深基坑全过程变形控制设计与实践

Design and Practice of the Entire Process Deformation Control of a Deep Excavation Under Complex Environments

上海城区建筑物密集、管线众多、高架及隧道纵横交错,地下工程开发需求量大,市区深基坑工程施工难度越来越高,传统的基坑工程设计施工由强度控制,在复杂环境条件下需由变形控制。以上海市中心某宾馆深基坑工程为背景,介绍在复杂环境条件下,运用勘察、设计和监测施工一体化的深基坑工程全过程变形控制思路。勘察阶段准确获取设计参数,设计阶段详细调查周边环境,采取有针对性的支护设计方法,施工阶段采用有效的降水方案和挖土措施,运用信息化监测手段,全过程控制基坑变形,保护周边环境。项目实施效果表明,采用全过程变形控制方法达到了预期目标,以期为类似深基坑的变形控制提供参考。

Shanghai is a rapidly growing city with densely distributed buildings,numerous underground utilities,and crisscross viaducts and tunnels in urban areas.With the great demand of the underground engineering development,the construction diffi-culty of the deep excavation is getting more and more demanding.The design and construction of the deep excavation support-ing system under complex environments has changed from the conventional strength control to the deformation control.Based on the deep excavation project of a hotel located in the center of Shanghai,this paper introduces the entire process deformation control idea of the deep excavation supporting system by integrating investigation,design monitoring and construction under complex environmental conditions.In the investigation phase,accurately obtain design parameters.In the design phase,inves-tigate surrounding environment in detail and adopt targeted support design method.In the construction stage,use effective de-watering schemes and dredging measures,timely adjust the construction scheme according to the monitoring data and control the deformation of the supporting system in the entire process to protect the surrounding environment.The results of the im-plementation and the monitoring show that the design and the entire implementation process achieved the expected goal,which can provide a reference for the similar deep excavation supporting system deformation control.