DEFLECTION PREDICTION OF TWO-SPAN CONTINUOUS CONCRETE BEAMS REINFORCED WITH GFRP BARS

Abstract

Continuous beams are main structural members in many reinforced concrete (RC) applications such as parking garages and bridges, which are vulnerable to harsh environments. The use of glass fiber-reinforced polymers (GFRP) bars in such structures has proven to be a good solution to overcome the steel corrosion problem. In GFRP-RC beams, deflection is a concern and may govern the design; thus, attempts have been made to propose models to predict the effective moment of inertia and consequently the deflection. The current prediction models were verified against deflection of simply-supported beams. In this paper, available predictions models are compared to the experimental deflections of two-span continuous beams. Eight rectangular beams (200×300 mm) continuous over two equal spans of 2,800 mm each were constructed and tested to failure. All beams were reinforced with GFRP bars and stirrups. The test variables included concrete strength, longitudinal reinforcement ratio and transverse reinforcement ratio. The comparison revealed that the investigated models reasonably predicted the deflection at service load level while they underestimated the deflection at higher load levels. These models require to be modified in order to yield better predictions of the deflection at lower and higher load levels than service load.