Foundation Reuse in Accelerated Bridge Construction

Abstract

When an existing bridge is being considered for replacement due to a deteriorated or obsolete superstructure, the foundation may still have significant functional value. Reuse of these foundations during bridge replacement or widening can present significant cost and time savings over constructing new elements. The potential time savings associated with foundation reuse can reduce mobility impacts, a key goal of accelerated bridge construction (ABC), and the cost savings can increase the economic viability and sustainability of an ABC bridge replacement project. However, existing foundations may have uncertain material properties, geometry, or details that impact the risks associated with reuse. Unlike a new foundation, an existing foundation may have been damaged, may not have sufficient capacity, and may have limited remaining service life due to deterioration. Assessment of these issues, possible foundation-strengthening measures, and innovative approaches to optimize loading are discussed in this paper. An analysis of an ABC database is performed to examine the current role of foundation reuse in ABC projects. This paper presents some key findings identified through various research projects related to foundation reuse. Six case examples are presented in which foundations were reused or considered for reuse during a bridge replacement project.