沉井结构在大型原水泵房中的应用及研究

Application and Study on Open Caisson Structure in Large Raw Water Pumping House

摘要:

在长江取水工程中，取水口的高度会对通航及河床稳定有直接的影响，因此在设计中一般会尽量降低取水口标高，这将会导致与之相连的原水泵房的埋深通常都比较深。在这种情况下，沉井施工工艺将比传统的基坑支护更有优势。通过具体的工程实例，阐述了沉井结构如何以带框架（或中隔墙）下沉的形式应用于较大型原水泵房，并对沉井在下沉阶段、水下封底阶段、顶管施工阶段及使用阶段中的稳定性及受力进行分析研究，为同类工程提供借鉴。

Abstract:

In the Changjiang River Water Intake Engineering, the height of intake will directly affect the navigation and the riverbed stability. Therefore, the intake elevation will be generally reduced as far as possible in the design, which will result in a buried depth of raw water pumping house connected with it usually deeper. Under this condition, the construction technology of open caisson will have more advantages than the conventional foundation pit supporting. Through the detailed engineering cases, the application of open caisson in the form of sinking with a frame (or middle partition) in the large raw water pumping houses is expounded. The stabilities and stresses of open caisson in the sinking stage, underwater sealing stage, pipe jacking stage and service stage are analyzed and studied, which can be referred for the similar projects.