摘要: |
The impact of the AASHTO Guide Specifications for Strength Evaluation of Steel and Concrete Bridges (STRENGTH method) on 40 steel and 33 concrete bridges in Missouri was investigated. The STRENGTH method is a reliability-based load and resistance factor rating procedure. The variable factors depend on levels of redundancy, deterioration, inspection, maintenance, truck volume, and weight enforcement, and selection of these factors is subjective, requiring considerable engineering judgment. The STRENGTH method considers site-specific loading and capacity characteristics to obtain consistent levels of safety over the bridge inventory. For bridges with good load and resistance characteristics, the STRENGTH method can significantly increase load ratings over current AASHTO load factor rating operating levels. However, deterioration and adverse traffic conditions can cause STRENGTH ratings to fall below load factor rating inventory levels. A method to evaluate the load capacity of concrete bridges that do not have detailed bridge plans is also investigated. |