In five years, after the bridge is built,
crossing the Yangtze River between the cities of Suzhou and Nantong will no
longer be an hour-long ferry ride. Instead it will be 5 minutes on the
world's longest cable-stayed bridge.
The foundation contractors at Sutong Bridge
faced some of the most challenging tasks in piling construction. Before the
piles were drilled to the depth of 395 ft, the steel casings were driven by
the largest vibro hammers available. Driving was through seven different
layers of ground consisting mainly medium dense to very dense fine sands,
with N values exceeding 60. Each casing weighted 135 tons with dimensions of
9.25 ft in diameter, 230 ft in length, and wall thickness of 1".
China Harbour Engineering Co., the major
contractor for the Sutong Bridge, awarded the contract to ICE for buying two V360
vibro hammers set up as a tandem to cope with the casing driving.
After the V360 tandem arrived the jobsite in the end of October 2003, it finished
driving of more than 200 casings within 6 months, an accomplishment exceeded the
most optimistic expectation!
