GANGED PIPE PIERS SUPPORT TRUSS BRIDGE IN DEEP WATER.

The paper reports how ganged pipe piers are overcoming swift ocean currents, deep waters and hard granite bedrock to support the main spans of a 3,366-ft-long continous truss bridge in western Japan. Each ganged pipe pier is a group of nine to 12 concrete-filled steel pipes over 13ft in diam, driven more than 40 ft into the ocean bed. The bridge has six piers of which three main piers are the ganged pipe piers and one is a concrete gravity-type pier on a mat foundation. Of the remaining two small piers, one was constructed inside a cofferdam and the other by sinking a small pneumatic caisson.