First Massive Concrete Base Slab for Lock Gate Cast at Dalu Line East Extension Navigation Hub

The first massive concrete base slab for the lock gate at the navigation hub of the Dalu Line East Extension Channel Improvement Project has been successfully cast. Located in Shanghai's Pudong New Area and the Lingang Special Area, the project involves the construction of new Class III twin-lane ship locks, a check gate, a saltwater prevention pumping station, traffic bridges, guide levees, and other supporting facilities. Upon completion, it will become Shanghai's largest inland river navigation hub.

The recently cast base slab, situated on the north side of the inner lock head for one lane, features a large structural size, densely arranged reinforcement, and strict temperature control requirements. The continuous concrete pour exceeded 2,000 cubic meters. The complex hydrogeological conditions of the construction area posed significant challenges for temperature control to prevent cracking and for on-site coordination.

To address the issue of heat hydration in mass concrete, the project team implemented a comprehensive "internal reduction and external preservation" temperature control strategy. This involved internal water circulation for cooling and external covering for insulation and curing. Smart sensors were utilized to monitor internal and external temperature differences in real-time, effectively preventing the formation of cracks.

Prior to the pour, the project team repeatedly optimized the concrete mix design, scientifically arranged cooling water pipes and an intelligent temperature monitoring system, and refined the construction technique of "layered pouring with sloping advancement."

Once operational, the hub will enable two-way navigation for thousand-tonnage container vessels. Inland river vessels will be able to travel directly to Yangshan Port via the Dalu Line channel, shortening the voyage by approximately 70 kilometers. This project is of great significance for promoting river-to-sea direct transport, advancing the high-quality development of inland waterways, enhancing the efficiency of the Yangtze River Delta's water transport network, and strengthening regional flood control capabilities.