An ALWAC footbridge over the river Gera near Rudisleben (Thuringia) -innovation in the design reinforced and prestressed concrete structures

摘要

In this paper, details of Innovative design, technology and construction of a footbridge in Thuringia (Germany) are presented. It is for the first time that prestressed concrete bars were applied as new reinforcing element The cube strength of the concrete used for concrete bars was about 130 MPa after 28 days and the modulus of elasticity(Ec )was 46000 MPa. For the superstructure an all lightweight aggregate concrete (ALWAC) LC 40/44 was chosen with an oven-dry density of rho =1.45 kg/dm~3. The combination of the new structural element on one hand and the high strength lightweight aggregate concrete on the other hand led to a favourable behaviour in the serviceability limit state with a significant decrease of deflection and crack width of the concrete superstructure. This behaviour could be demonstrated during different static and dynamic tests. The pilot project was completed by using a high strength concrete (C70/85) with normal density for the concrete columns.