St. Andrews Lock and Dam Bridge Deck Replacement

Associated Engineering undertook the comprehensive detailed inspections in 2019 to inform the rehabilitation and strengthening design. The objective of the rehabilitation was to remove the load posting on the bridge, which was posted at 36 tonnes, complete the deck rehabilitation on both approach structures, complete new deck and stringers on the main truss spans (spans 1 through 7), widening of existing deck to the north, and replace expansion bearings on pier 1.

Detailed analysis was undertaken in order to fully understand the nature of the existing structure, taking into account material properties from a hundred years ago, and how it is configured. This understanding was key to developing an appropriate design response to rehabilitate, strengthen, and widen the structure. The detailed analysis included a structural evaluation taking into account reductions in structural capacity of existing deteriorated members. The structural evaluation was completed to determine deficient members that would need upgrading for the anticipated load demands and widening.