Optimal Maintenance of Below-Grade Culverts

In Israel, below-grade culverts are critical structure as they are essential points of the water transport network across the country. A lack of maintenance may create safety hazards and economic loss. The current maintenance strategy is that of breakdown maintenance. Such strategy has the drawback of high repair and maintenance costs. This study presents a methodology to determine the optimal maintenance strategy for below-grade culverts during their design life, by evaluating life cycle performances and life cycle costs. A field survey aimed at collecting critical data to develop a suitable deterioration pattern model. An exponential model was found to be the most significant statistically. A Markov chain model was implemented to determine the culvert life cycle performances and life cycle costs. A Maintenance Effectiveness Indicator (MEI) determines the best life cycle maintenance strategy among: breakdown, performance-based, and preventive maintenance. The best maintenance strategy was found to be the preventive. It provides with the highest cost effectiveness and allows for knowing the required budget in advance. Preventive maintenance strategy, which is strongly associated with Lean Construction, permits to save 80% of the resources required under the breakdown maintenance regime. The methodology can be extended to other assets of the roadway infrastructure.