狭长型深基坑支撑围护体系设计与施工过程中需考虑空间效应。本文以上海某狭长型深基坑为例，探讨在确保基坑安全前提下支撑围护体系的优化与深基坑施工策划。首先，介绍了初始围护设计方案及对应的深基坑施工方案；其次，提出在基坑长边中部增加地下连续墙作为中隔墙，形成分坑施工的围护方案，并进行相应的施工策划；随后，对两种支护体系下的工期节点、基坑安全及经济与社会效益等进行对比。研究发现，增加中隔墙对支撑围护直接成本有所增加，但对于确保基坑安全、强化工程关键路线、减小对周边环境的影响等方面均有帮助。

The spatial effect should be considered in the design and construction of long and narrow deep foundation pit. Taking a long and narrow deep foundation pit in Shanghai as an example, this paper discusses the optimization of the supporting and retaining system and the construction planning of deep foundation pit. Firstly, the initial enclosure design scheme and corresponding deep foundation pit construction scheme are introduced. Secondly, it is proposed to add underground continuous wall in the middle of the long side of the foundation pit as the middle partition wall, and the corresponding construction planning is carried out. Then, the construction period nodes, foundation pit safety, economic and social benefits under the two support systems are compared. It is found that adding the middle partition wall increases the direct cost of the support and enclosure, but it is of great help to ensure the safety of the foundation pit, to strengthen the key route of the project and to reduce the impact on the surrounding environment.

TU753