The invention discloses a
cofferdam construction method combining film bag sand filling with a steel
sheet pile. The
cofferdam construction method comprises the steps of measurement and alignment, film bag positioning and laying, layer-by-layer film bag sand filling, muddy water discharging to enable a film bag sand
cofferdam to precipitate, blow filling of closed sand between two
layers of film bag sand,
water pumping and drainage in a cofferdam foundation pit, steel
sheet pile anti-seepage core wall construction and the like. According to the construction method, the film bag sand filling is combined with the steel
sheet pile anti-seepage full-section cofferdam, the upper portion of the cofferdam is piled up with the film bag wrapped with sand soil, the lower portion of the cofferdam is anti-seepage through the steel sheet piles, the whole cofferdam becomes a whole, so that the cofferdam is high in integrity, good in
self stability, high in adaptability to foundation, high in
water pressure resistance and good in anti-seepage effect. The problem that the construction cofferdam is constructed under complex
underwater geological conditions can be basically and effectively solved, the overall stability of a cofferdam structure is improved, and the cofferdam construction method has the advantages of being simple in process, fast in construction progress, low in cost and the like and has wide application prospects in the field of cofferdam construction of water conservancy projects.