New Framework for Risk-Based Inspection of Highway Bridges

Abstract

This paper presents a new methodology for determining bridge inspection intervals and procedures. The methodology was developed using established risk-based methodologies with the goals of improving bridge safety and serviceability and optimizing the use of resources for bridge inspection. Current inspection intervals are calendar based and generally require routine inspections at a maximum interval of 24 months. This uniform, calendar-based approach results in the same inspection interval for new bridges and aging and deteriorated bridges. The uniform inspection interval does not consider the inspection needs for a given bridge based on age, condition, materials, environment, etc., and as a result, inspection resources may not be utilized most effectively. Using the methodology described in this paper, a bridge owner performs a simple risk-based assessment of bridges in his or her inventory to identify those for which shorter inspection intervals are needed and those for which longer intervals are more appropriate. This assessment identifies likely damage modes and associated consequences in terms of safety and serviceability of a bridge. A simple risk matrix is used to identify the appropriate inspection interval for bridges. The new, risk-based approach represents a new paradigm for bridge inspection that could transform traditional, uniform, and calendar-based inspection approaches and improve the allocation of resources for bridge inspection to improve the reliability and safety of bridges.