Patent ID: 6926470

Claim:
A rolled steel sheet pile, comprising: a first end flange; a second end flange; a first joint formed at an edge of said first end flange; and a second joint formed at an edge of said second end flange, each of said first and second joints including a connecting portion, a bottom portion, and an engaging edge portion, the connecting portion, the bottom portion and the engaging edge portion forming a fitting groove, a protrusion being formed on a fitting groove side of the connecting portion, and the engaging edge portion is for being received into a fitting groove of an adjacent rolled sheet pile to form a pair of interfitted joints, wherein a cross-sectional shape of said first and second joints is line-symmetric or point-symmetric, said first and second joints are designed so that a center of a point of symmetry of the pair of interfitted joints is located on or near a centerline of said first and second end flanges, respectively, in a thickness direction, and said first and second joints are designed so that a contact surface formed between the engaging edge portions of the pair of interfitted joints is a line contact and an axis of the line contact inclines toward the protrusions of the pair of interfitted joints.