Operational Structural Performances of Bridge Materials by Areas

Abstract

This paper evaluates the operational structural performances of the various kinds of bridge construction materials and/or structural designs, considering the deck areas of bridges, rather than their discrete counts. Deck areas represent more objectively the actual constructed capacity in the inventory and the traffic mobility. The study compiles and analyzes the entire bridge inventory in the United States. The analysis uses multiple-criteria diagnostic measures to determine the condition, durability, longevity, and overall equivalent performances. The results provide a comprehensive national network-level comparative basis for bridge material performances at the serviceability limit states. Nearly 99% of all the bridge areas in the inventory have average structural deficiency ages significantly lower than the official life-cycle expectancy. The durability performances indicate that the average service life before structural deficiency is only 42 years. The relatively high condition contrasts with the low durability and longevity performances, reflecting the efforts to improve the condition of bridges. Overall, the average equivalent structural performances of bridge materials by deck areas are quite low, and even lower as compared with performances by bridge counts.