Cape Cod Canal Bridge Rehabilitation

The Cape Code Canal Railroad Bridge holds several distinctions. The gateway structure to the world’s widest sea level canal is also the second longest lift bridge in the United States. The continued operation and maintenance of this railroad vertical lift bridge provides vessels with access through the canal, saving an average of 135 miles of coast-wise travel around the tip of Cape Cod. The New England District of the U. S. Corps of Engineers needed someone to evaluate their valuable asset to maximize reliability. At the same time, the firm had to be able to perform the tasks with minimal disruption to both rail and ship traffic. 

 

Modjeski and Masters (M&M) brought an integrated approach to providing the required multi-dimensional movable bridge services. Our structural, mechanical and electrical engineers and inspectors brings innovation to the inspection process by incorporating technical and rope access climbing techniques to minimize rail and shipping interruptions. Our initial assignment was for a complete inspection that included mechanical, electrical and structural members. With findings in hand, we developed load capacity ratings and a fatigue evaluation. Soon after M&M developed contract documents for a complete rehabilitation of the bridge, which included structural, mechanical and electrical components. Under normal circumstances, construction progresses with the movable span in the lowered position. However, operational constraints required that all rehabilitation be performed with the lift span in the raised position. It was critical that construction time be minimized with limited interference to navigation. Swift and changing currents in the canal precluded the use of “float-out / float-in” procedures. Our engineers developed temporary supports for the lift span which allowed a first-ever replacement of counterweight ropes with the span in the raised position and the counterweights supported from the tower tops.