Deck Slab Elements for the Accelerated Construction of Steel–Concrete Composite Bridges

Abstract

Various methods have been developed to produce deck slabs for steel–concrete composite bridges. Usually, the deck slabs are cast with in situ concrete using a formwork carriage, resulting in construction progress of 15 to 25 m of deck slab per week. A new construction method was developed at the Institute of Structural Engineering (TU Wien), which enables the swift erection of the concrete deck slab. This method employs precast deck slab elements with reinforced concrete cross-beams which span in the transverse direction. With this new construction method, producing up to two deck slab sections of 15–25 m per day becomes possible. Further, the performance of novel reinforcement detailing required for the precast deck slab elements is investigated by structural testing. The experiments consist of eight load-bearing tests on four specimens which represent sections of the element during casting and after completion. The investigated parameters in series 1 are the length and spacing of loops, used for protruding longitudinal bars enclosure. In series 2, the enclosure of the shear reinforcement and the height of the cross beams are varied. The results show that the targeted bending capacity could be reached in all tests with no signs of premature failure due to detailing reasons. Based on the experimental results, the feasibility of the new approach is shown and recommendations for detailing are given.