Nonmetallic reinforcement at the cap widening of Carola Bridge in Dresden

Abstract

The Carola Bridge (Carolabrücke), built in 1971, has a length of approximately 375 m and takes the tram and the B 170 federal road in Dresden across the river Elbe. The intensive use of the bridge and deficits in user‐friendliness made building measures inevitable. One part was the widening of the upstream bridge cap. Here, the application of a new nonmetallic reinforcement within the concrete cover was planned to improve the service life of the cap, a so far unique method. Based on an installation test and an investigation of the cracking behavior, both described in the paper, two reinforcement configurations were selected for practical application. The project provides an ideal opportunity to bring carbon and basalt reinforcements closer to the public and to demonstrate their cast in during normal operation on a concrete construction site.

Investigation on the crack formation in carbon concrete for the use in deck caps on cantilever slabs of bridges

“…Alternatively, biaxial load‐bearing textiles with larger mesh sizes, which seem more suitable for use with a deck cap concrete that has a maximum grain size of 8 mm, should be tested in further investigations. For example, such textiles found in‐situ application during the refurbishment of the Carola Bridge in Dresden, see References [5,6]. Furthermore, the selected test setup, for example, the clamping and measuring length, is essential when generating test results.…”

“…By using a corrosion-resistant carbon reinforcement, the concrete cover can be significantly reduced compared to conventional steel-reinforced deck caps. 5,6 Due to a higher concrete strength in combination with a decreased concrete cover and an increased tensile strength of the carbon reinforcement, the occurring restraint stresses can be absorbed and a finely dispersed crack formation can be achieved. All these effects improve the durability of these structural elements.…”

“…To prevent this, a thick concrete cover is required to protect the steel which can also raise problems in the deck caps with small dimensions. By using a corrosion‐resistant carbon reinforcement, the concrete cover can be significantly reduced compared to conventional steel‐reinforced deck caps 5,6 . Due to a higher concrete strength in combination with a decreased concrete cover and an increased tensile strength of the carbon reinforcement, the occurring restraint stresses can be absorbed and a finely dispersed crack formation can be achieved.…”