Strength behavior of filled steel grid decks for bridges

Abstract

The life cycle of grid decks has come full circle from their introduction in the 1920s and 1930s through their maturity in 1950s and 1960s to their reintroduction in the 1980s. Many of these decks have been performing satisfactorily over 50 or more years of service. Filled grid decks offer a lightweight and high strength deck alternative to reinforced concrete decks. Despite the good performance history of grid decks, some bridge owners are hesitant to utilize them. With a better understanding of grid deck behavior, the manufacturing process can be optimized, and design method improved. Hence, poor details can be avoided and design efficiency can be achieved. This paper presents results of research conducted with the goal of providing a better understanding of filled steel grid deck behavior through experimental testing and numerical analyses. Three full-scale filled grid decks were tested to experimentally quantify their structural behavior. Three-dimensional finite element (FE) models were developed for the grid decks and calibrated using the experimental results. Finally, parametric studies were conducted and used to quantify the effect of variations in the significant design parameters. The results of the parametric studies can be applied to optimize future grid deck designs. It should be noted that crack width and ductility are important serviceability parameters in the performance of filled steel grid bridge decks. However, the work described in this paper is limited to strength issues and does not include evaluation of serviceability parameters.