New Piers for an Old Bridge

Placing new piers under an old superstructure has saved the architecture of the historic Ashley River Bridge in Charleston, S.C. In July 1987, an inspection indicated deterioration and loss of section in the piers and the bridge was posted. The state highway department and consultants determined that, because the superstructure was stable, its loads could be transferred to new piers built adjacent to the old. Specially designed falsework and casting procedures were required to support the weight of the new cap-transfer beam concrete as it was being cast. The load transfer was done with multiple reaction jacks at each end of eacn new cap beam, with new bearings grouted into place after jacking. To speed the project, the state required each bidder to quote a construction completion date as well as bid price. A $5,000/day penalty liquidated damages provision was stipulated. The project ultimately replaced 18 piers within one calendar year.