2017 Ship Lock Project of the Lishui Section of the Oujiang River Channel Improvement Project

Lishui Port and Shipping Construction Development Co., Ltd.

The Second Construction Section of the Lishui Section of the Oujiang River Channel Improvement Project (from Baiyan Bridge on Lishui West Ring Road to the downstream of Wai Xiong Power Station Dam) involved the construction of 123 caissons, including 28 caissons for Kaitan Ship Lock, 58 caissons for Wuliting Ship Lock, and 37 caissons for Wai Xiong Ship Lock.

The caissons for Wuliting Ship Lock and Wai Xiong Ship Lock were prefabricated at the Xiaoqun Village Precast Yard, while those for Kaitan Ship Lock were prefabricated at the Kaitan Downstream Precast Yard. The caissons were launched into the water through a slipway, transported to the construction site by floating vessels, and then installed in position.

This project featured a wide variety of caisson types and large structural dimensions, with complex construction techniques. The maximum caisson weight reached 235 tonnes, making it the first project in China to apply caisson construction technology in an inland river navigation project.

Based on the characteristics of mountainous inland waterways, the key challenge of this project was to address the difficulties of caisson prefabrication, launching, transportation, and installation under complex and restricted construction conditions.

Through the implementation of this project, effective solutions were developed for caisson launching, floating transportation, positioning, and installation in mountainous inland waterways with limited water depth, significant water level fluctuations, and restricted access for large construction vessels. The project successfully overcame the technical challenges of caisson construction in mountainous river navigation projects.

The application of this technology significantly reduced underwater construction works, accelerated construction progress, and improved the overall structural stability. It also promoted the application of caisson structures in inland waterway engineering and provided valuable technical experience for similar projects.