Germany's first application of UHPFRC in railway bridge construction Part 2: Accompanying scientific investigations and measurement supervision of manufacture and in operation

Ultra-high performance fibre-reinforced concrete (UHPFRC) is characterized by an extremely dense microstructure and thus very high strengths as well as excellent durability properties. This enables a material-saving and weight-reduced, slim construction method that opens up completely new possibilities and areas of application in precast bridge construction. In the course of the superstructure renewal of an existing railway bridge the material could now be used for the first time in Germany for a railway bridge in a particularly practical and advantageous way. The superstructure was designed as a trough-shaped precast slab bridge in prestressed concrete construction with a very low construction height. This part 2 of the article deals on the one hand with accompanying experimental investigations on crack formation and on the flexural behavior of a purely steel fibre reinforced mock-up of the bridge superstructure. On the other hand, the technical paper deals with the measurement supervision of manufacture and in operation. In addition to determining losses of prestress and hydration heat development, structural measurements were also carried out to determine the real structural responses in the course of test loads with defined axle loads.