Semi vertical type cofferdam structure and construction method thereof

The invention discloses a semi vertical type cofferdam structure and a construction method thereof. The semi vertical type cofferdam structure comprises a backfill earth rock material, a surface cover, a foundation structure, a sheet pile, a supporting pier and a supporting rod. The sheet pile is arranged at one end of the foundation structure, the slope type surface cover is arranged at the otherend of the foundation structure, the backfill earth rock material is arranged between the slope type surface cover and the sheet pile, and the backfill earth rock material is located on the upper portion of the foundation structure; and one end of the supporting rod is connected with the top of the sheet pile, and the other end of the supporting rod is connected with the supporting pier. According to the semi vertical type cofferdam structure, the outer side earth rock cofferdam and inner side sheet pile foundation pit support are adopted to conduct combination, thus the semi vertical type cofferdam structure is join