Evaluating Bridge Substructures for Structural Integrity and Durability

Increasingly, in bridge widening and replacement projects, engineers are considering foundation reuse or, if retaining the same bridge alignment, the reuse of the whole substructure element, including foundations, piers, and walls. Foundation reuse projects are particularly beneficial in urban areas due to high mobility and traffic demands. A notable application includes pairing foundation reuse with accelerated bridge construction technologies for superstructure replacement — such as using prefabricated bridge elements and systems. The obvious rationale is cost savings, but other factors, such as decreased construction time, sustainability considerations like reduced carbon emissions, reduced site impacts, and historical preservation, are also important considerations. However, reuse has its challenges, not the least of which is to accurately assess the structural integrity, durability, and the capacity of existing foundations, because it's essential that reused foundation elements function at least as acceptably as the superstructure elements they will bear for the remainder of their expected service life.