| 摘要 |
PROBLEM TO BE SOLVED: To improve the long period adhering property of a sheet pile in marine water by setting the Vicat softening point of a modified polyolefin layer within a specified range, in a heavy duty protective coated steel sheet pile, consisting of the integrated sheet of modified polyolefin layer and corrosion resistant polyolefin layer, bonded on the heated steel sheet pile. SOLUTION: A heavy duty protective coated steel sheet pile 1, at least on side of the same is coated by a corrosion resistant polyolefin layer 4 through modified polyolefin layer 3, is employed for the steel sheet pile, forming the wharf of marine, harbor, river and the like. In this case, the modified polyolefin, having the Vicat softening point of higher than 50 deg.C and lower than 90 deg.C, is employed. On the other hand, in manufacturing the steel sheet pile 1, substrate treatments, such as degreasing, acid washing, shot-blast treatment and the like, are applied previously preferably to remove oil constituents, scales and the like on the surface of the steel member, then, the organic resin based primer or a primer layer 2, prominent in the adhering property to the surface of steel sheet pile and the modified polyolefin layer, is applied on the surface of the same. |
