Durability of RC Beams Strengthened Using GFRP-Sheet due to Fatigue Loads

Abstract

This paper presented the results of an experimental study of the behaviour of flexural beams strengthened with the glass fiber reinforced polymer (GFRP-S). This research was carried out to determine the effect of fatigue loads on the flexural capacity of reinforced concrete beams. The specimens were rectangular with a dimension of 150 mm in width, 200 mm in height, and 3300 mm in length. Four distinct conditions had been applied to this experiment. For the initial condition, two beams were tested under monotonic loads (maximum load control) as a control beam (BN). Sinusoidal fatigue loads were applied to four specimens from 4 kN to 24 kN (BF). Our comparative results of the experiment had presented that the normal beams (BN) failed after 800,000 loads cycle, while, the reinforced beams with GFRP (BF) failed after 1,231,860 loads cycle. Based on our results, it can be stated generally that fatigue life of the reinforcement beams (BF) could increase to more than 100% compared to that of the normal beams (BN). The failure of the beams is probably caused by fatigue of the reinforcement bar and debonding of the GFRP-S, both are secondary failure mechanism of reinforced concrete beams.