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

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

Abstract

Deck caps of bridges—in Germany shortly known as “bridge caps”—are usually made of steel reinforced concrete to form the anchoring area for the guardrail of bridge deck edges on existing cantilever slabs. Combined with protective devices, the outside arranged deck caps provide safety against lateral breaking or crashes of vehicles. Due to their exposed position in the cross section of bridges and the particularly intensive stresses, the deck caps are considered as wear parts and have to be renewed several times during the service life of a bridge. The decisive factor here is the discrepancy between the frost resistance of the concrete and the crack width restriction. On the one hand, only very small cracks (<0.2 mm) can be accepted to prevent corrosion of the rebars under the strong exposure of these elements. To confine crack widths without applying an excessively high degree of reinforcement, a low concrete compressive strength is advantageous. On the other hand, a sufficient frost resistance requires a correspondingly high compressive strength. With carbon reinforcement, these contrary points could be defused and simultaneously the needed durability could be provided. Therefore, slightly modified deck cap concretes combined with a carbon reinforcement mesh were tested to examine the bond behavior with and without freeze–thaw attack. To prove the characteristics of this combined system, the crack formation and crack distribution were investigated experimentally. The test results were compared to calculated values from a mathematically tool to be able to develop different reinforcement concepts in future that can ensure an optimized crack formation and crack width for deck caps.

Details

OriginalspracheEnglisch
Seiten (von - bis)2563-2574
Seitenumfang12
FachzeitschriftStructural concrete
Jahrgang24
Ausgabenummer2
Frühes Online-Datum9 Sept. 2022
PublikationsstatusVeröffentlicht - Apr. 2023
Peer-Review-StatusJa

Externe IDs

ORCID /0000-0001-5645-9652/work/159606364
ORCID /0000-0002-1596-7164/work/159608547

Schlagworte

Schlagwörter

  • carbon reinforced concrete, carbon reinforcement mesh, deck caps of bridges (resp. bridge caps), durability, freeze–thaw resistance

Bibliotheksschlagworte