Lock catch steel pipe pile and I-shaped plate pile combined cofferdam structure and construction method thereof

The invention discloses a lock catch steel pipe pile and I-shaped plate pile combined cofferdam structure. The lock catch steel pipe pile and I-shaped plate pile combined cofferdam structure comprisesa plurality of lock catch steel pipe piles which are mutually spliced end to end, and a plurality of I-shaped lock plates; two or more C-shaped lock catches are mounted on the outer side wall of eachlock catch steel pipe pile; and the two ends of each I-shaped lock plate are clamped and inserted into the C-shaped lock catches of the two corresponding adjacent lock catch steel pipe piles correspondingly, and thus the two adjacent lock catch steel pipe piles are connected. By adopting a lock catch steel pipe pile and I-shaped plate pile combined structure form, the construction work efficiencyis improved while the engineering construction cost is lowered; and the lock catch steel pipe piles and the I-shaped plate piles are connected through the C-shaped lock catches, thus the structure issimple, connecting is reliable, and integrity of a cofferdam is improved.