Steel sheet pile is a type of steel with a lock. Its cross-sections include straight plate, groove and Z-shaped, etc., and are available in various sizes and interlocking forms. Common ones include Larson type, Lackawanna type, etc. Its advantages are: high strength, easy to drive into hard soil; it can be constructed in deep water, and if necessary, diagonal supports can be added to form a cage. It has good waterproof performance; it can form cofferdams of various shapes as needed and can be reused many times. Therefore, it has a wide range of uses.