福州市某污水处理厂进水泵房沉井施工案例

Construction of Open Caisson in Inlet Pump House of a Wastewater Treatment Plant in Fuzhou City

摘要:

福州市某污水处理厂建设工程进水泵房沉井施工工程采用分次制作、二次下沉、水下封底的方法，并且为控制沉井在淤泥层接高时的稳定性，提前在刃脚和中隔墙底施工8%水泥含量的搅拌桩。以该工程为例，介绍了沉井分次制作、分次下沉的施工程序和技术要点，包括分节制作高度、刃脚垫层设置、取土下沉方法、淤泥层沉井接高止沉方法、脚手架搭设方法、沉井封底方法、纠偏方法等。经验证，该工程沉井施工质量达到了控制标准要求，可为类似工程沉井下沉施工提供借鉴。

Abstract:

The open caisson in inlet pump house of a wastewater treatment plant (WWTP) construction project in Fuzhou is constructed with the methods of staged fabrication, secondary sinking and underwater bottom sealing. To control the stability of the open caisson during the elevated in the mud layer, the 8% cement content mixing piles are constructed at the edge of the blade and the bottom of the middle partition wall in advance. Taking this project as an example, the construction procedures and technical essentials of staged fabrication and staged sinking of the open caisson are introduced, including segmental fabrication elevation, setting up edge foot pad layer, soil removal sinking method, open caisson elevated and anti-sinking method in the mud layer, scaffold erection method, open caisson bottom sealing method, and correction method. It has been verified that the construction quality of the open caisson in this project meets the control standard requirements and can provide reference for the construction of similar open caisson sinking projects.