苏通大桥挑战与创新

由于复杂的气象条件和地理环境,建设苏通大桥是一个巨大的挑战.苏通大桥采用2.85m大直径工程钢护筒作为支撑桩成功搭设施工平台,将平台误差控制在5cm以内,将100m长桩的倾斜度控制在1/200以内;将临时结构钢套箱用作防船撞结构,有效解决桥墩防撞安全问题;采用集中控制的千斤顶群顶技术实现了双向潮汐河段6000t钢套箱整体沉放,同步误差控制在1cm以内;采用临时防护与永久防护相结合的冲刷防护方法,有效抑制河床冲刷,保证了基础施工和运营安全;采用温度与风修正和追踪棱镜法解决了索塔施工测量与控制难题,提高了复杂条件下高耸结构施工测量工效,将300m索塔施工误差控制在10mm以内,倾斜度控制在1/40000以内.

Challenge and innovation of Sutong Bridge

The construction of Sutong Bridge is a big challenge due to the complicated meteorological and geological conditions. To confront this challenge, steel casing with a diameter of 2. 85 m is utilized as support to establish construction platform with a tolerance of 5 cm. Verticality of 100 m long bored piles are successfully controlled within 1/200 tolerance. Steel cofferdam is adopted as a temporary structure to protect structure against ship collision so as to effectively ensure bridge pier's safety. Sutong Bridge adopts jacking operation by multiple centralized jacks, realizes lowering of 6000t steel cofferdam as a whole in dual direction tidal reach and achieves synchronized tolerance within 1cm. Sutong Bridge implements scour protection with combination of temporary protection and permanent protection , which effectively controls riverbed scour and ensures safety of foundation construction and operation. Sutong Bridge overcomes the difficulty of measurement and control during construction of pylon by means of wind and temperature induced correction as well as tracking prism, which helps to improve survey accuracy of towering structures under complicated conditions. To be exact, the construction tolerance for 300 m high pylon has been controlled within 10 mm and verticality of pylon has been controlled within 1/40000.