Durable transition structure for long integral abutment bridges

摘要

The construction of integral abutment bridges is becoming more common. Since these bridge structures have no expansion joints or bearings, it is possible to build low-maintenance and long-lasting structures. The length of most existing integral abutment bridges does not exceed 20m, but larger lengths are also increasingly being implemented. Structures up to approximately 70m are considered to be unproblematic. In longer integral abutment bridges, problems often occur in regard to surface cracks and settlements behind the abutments. To address these challenges, intensive research work has been conducted. A new jointless roadway transition structure for long integral abutment bridges has been developed at the Institute of Structural Engineering of TU Wien. The design principle of the new transition structure is based on the distribution of the deformations, which occur in the bridge due to temperature changes, shrinkage, creep, and external loading, over a longer area behind the abutment. Because the deformations are distributed, it is possible to build a seamless pavement structure across the expansion joint, from the bridge to the embankment. The Research Center for Road Engineering, TU Wien, has developed a special multilayer bituminous pavement structure just for this purpose. Based on the design considerations for the transition structure, a full-scale prototype was built. The prototype was tested at various construction stages to obtain relevant data for practical use.