Punching behaviour of a hybrid reinforced concrete bridge deck

Abstract

Deterioration of concrete structures subjected to aggressive environmental conditions is attributed to corrosion of the steel reinforcement. Highway bridge deck slabs in particular are exposed to de-icing chemicals that attack the internal reinforcement after the initiation of cracks on the top surface. The use of glass-fibre reinforced polymer (GFRP) bars as top reinforcement in the deck slab greatly increases the resistance of the deck slab to corrosion. Conventional steel bottom reinforcement allows the structural deck system to achieve an overall ductility close to that of a conventional steel-reinforced bridge deck. This hybrid reinforcing system presents a compromise between corrosion-free FRP reinforcement, with low ductility and high cost, and ductile, inexpensive conventional reinforcement, with poor corrosion resistance. This thesis presents the experimental program of a full-scale hybrid-reinforced bridge deck model. Five static tests were conducted using a simulated design wheel loading to investigate the suitability of a hybrid reinforcing system for highway bridge deck slabs. The behaviour of the experimental model is evaluated and compared with other experimental and analytical models as well as code predictions. Based on this investigation, recommendations are made regarding the applicability of hybrid reinforcement for concrete highway bridge decks.