Structural Behavior Of Thin Prestressed Slab Beams In Bridges

This research was carried out to investigate the behavior of thin prestressed slab beams (TPSBs) that are part of the Department of Transportation's inventory, including TxDOT. Fourteen TPSBs were tested to study the structural behavior and the effects of several variables, such as height, cast-in-place deck, shear span-depth ratio (a/d), prestressing steel ratio, transverse steel ratio, and longitudinal reinforcement at the prestress-transfer zone. The tests showed that shear was not the predominant failure mode, even under very small shear span-depth ratios (a/d approximate to 1.2). In most cases, failures of TPSBs were governed by either anchorage bond or flexure.When compared to the current building and bridge codes, the test results showed that both ACI 318 and AASHTO LRFD cannot predict the strength and the failure mode of TPSBs reasonably. As a result, a design equation is derived based on anchorage bond and flexural capacities.