Waterstop steel plate, also known as steel waterstop, or waterproof steel plate, is typically made by straightening and bending coiled steel strips. After the foundation is laid, waterproof steel plates or waterstops are required between construction joints for waterproofing. Generally, a single waterproof steel plate is 3 meters long and is used in construction joints and expansion joints on the site, welded into the construction joints to provide waterproofing.

In the base or basement of the container, the concrete for the bottom plate and exterior wall panels, and the roof deck is cast separately. When pouring the concrete for the wall panels again, there is a construction cold joint. If this joint is below the groundwater level, it is prone to leakage. Technical treatment of this joint is required, and there are many methods available. One common approach is to install a waterstop steel plate.