Old Concrete Slab Bridges. II: Analysis

Abstract

Old reinforced concrete slab bridges designed for smaller truck loads are called on to carry modern, heavier loads. These bridges, when rated according to current American Association of State Highway and Transportation Officials procedures are found to be structurally deficient. Therefore, it is important to rate these bridges more realistically. The experimental part of the investigation to understand the behavior of slab bridges is given in a companion paper. The present paper provides the analysis of the experimental data. The reasons for the conservatism of the current rating procedures observed during the experimental investigation stemmed from the facts that the actual material properties were much higher than the assumed design values, and the curbs participated to a considerable extent in carrying the applied loads. Also, a simple three‐dimensional finite‐element model to analyze these bridges under service loads is presented.