Construction of Akashi-Kaikyo bridge west anchorage

The Akashi-Kaikyo suspension bridge, with a central span of 1,990 m, will soon become the world’s longest single span. In total, some 1,420,000 m3 of concrete will go into two piers and two anchorage substructures. Two steel towers will rise to 297 m above sea level; 200,000 t of steel will form the superstructure. Twin cables, each 1.1 m in diameter, will support up to 118,000 tons. Design criteria should enable the bridge to survive earthquakes of magnitude 8.5 and winds of over 80 m/s. Started in 1988, it is scheduled for completion in 1998 at a cost of $3 billion. This paper begins with an overview of the bridge, but concentrates on construction of the west anchorage (1A), recently completed. This anchorage was built within a 75.5-m deep, 2.2-m thick concrete slurry wall. Mass concrete within the 85-m diameter retaining wall was placed from a depth of 64.5 m using roller-compacted concrete. Design details, production methods, automated instrumentation, and data-collection systems are described.