Performance Evaluation of Empirically and Traditionally Designed Bridge Decks

Abstract

The focus of this study is to assess the performance of empirically designed reinforced concrete bridge decks versus those designed using traditional analytical design methods and to check the adequacy of both design methods by correlating the theoretical results with field observations. A case study of Buffalo Creek Bridge was selected for this study, because it was originally constructed with an empirical deck that developed severe cracking and required demolition, and was reconstructed again with a traditional deck. Three-dimensional finite-element modeling of the Buffalo Creek bridge superstructure was developed, taking into consideration real-life loading configurations of environmental loads. Both the empirical deck and the current traditionally designed deck were modeled and the state-of-stress developed in each design was identified. The connections between the steel main girders and the concrete deck were identified as the primary constraints for deck expansion and contraction in the transverse direction; hence, high tensile stresses were developed over the girders in the transverse direction. Additionally, the sharp edge of the clip angle protruding into the concrete deck, in addition to the top of the slope of the stay-in-place forms, were identified as stress risers that contribute to the longitudinal cracking problem. Therefore, additional reinforcement is needed in these areas to control the occurrence of such cracks.