Key technology and innovation of Sutong Bridge

Sutong Bridge is the first cable stayed bridge with the span exceeds 1 000 m which located in the mouth of Yangtze River. Its pylon foundation located in the river where the water is deep and current speed is high, and adopted the bored group piles foundation which is the largest group piles foundation. To the group piles foundation with the construction condition of deep water and high speed current, the exactly construction of the steel cofferdam which provided dry condition for the pile caps construction is a problem. This paper discussed the lowering as a whole technology of Sutong Bridge 5 800 t weigh steel cofferdam from 6 respects such as selection of lowering scheme, design, fabrication, lowering techniques, synchronousness controlling and orientation. In which, the design combined the coping of bored piles construction platform with bottom of steel cofferdam, the lowering as a whole techniques, synchronousness controlling and orientation technology are innovation.