It has equal substance and good cross section. The product has superior substance (yield point: 345 N/㎟ and above) and good cross section performance, since the production is made by Cold Roll Forming using hot coil produced by POSCO. The working is easy and the term of works can be shortened. Term of works can be shortened due to outstanding workability by high stiffness and wide width. In constructing at general soil x-layer, the work is easy due to no dip and no common drop. It is economical. It is economical since required steel quantity per unit area compared to cross section performance can be minimized. In constructing vertical counterflow prevented grouting wall, much budget reduction is possible. Sea water resistance steel (A690 steel) can be used. Sea water resistance steel, which can form the weatherability structure with improved durability, can be selected for construction work for ocean structures such as bank inside wall, and seashore deck protection work.