FAST ERECTION OF DECK SLABS FOR STEEL-CONCRETE-COMPOSITE BRIDGES

Abstract

Different methods have been developed for the production of deck slabs of large steel-concrete-compo-site bridges. Often such deck slabs are cast with in-situ concrete with the aid of a formwork carriage. The formwork of the deck slab is supported by the formwork carriage, which can be moved longitudi-nally along the bridge. Placing of the reinforcement takes place at the installation site resulting in a construction progress of 15 m to 25 m of deck slab per week. In order to speed up the construction, construction methods with precast partial-depth or full-depth elements have been employed. Usually, a crane is needed for the placing of the prefabricated elements. A big disadvantage of the construction with precast deck elements is the fact that a supporting steel structure has to be provided. Cantilevering transverse steel girders have to be installed in the bridge deck, whose sole purpose is to support the precast elements. A new construction method was developed at TU Wien, which enables a very fast erection of the con-crete deck slab and which avoids the installation of additional transverse steel girders. In this method, precast deck slab elements with reinforced concrete cross-beams are employed. The precast deck slab elements are placed on top of the steel girder with the aid of a novel transportation carriage. The trans-portation carriage consists of two parts, which are connected by two longitudinal trusses, and can be moved longitudinally along the bridge. The new construction method, which will make the production of one section of the deck slab per day possible, will be described in detail in the paper.