Steel sheet pile is a type of steel with a lock, and its cross-section is straight, grooved and Z-shaped, and has various sizes
and interlocking forms. The common ones are Larson, Lackawanna and so on. Its advantages are: high strength, easy to drive into
the hard soil layer; can be constructed in deep water, if necessary, add inclined support to become a cage. Good waterproof
performance; can form cofferdams of various shapes as required, and can be reused many times, so it is widely used.