Durability of Concrete Beam Strengthened with Fibwrap ® System and Fiber Composite Laminate

Abstract

Externally bonded fiber-resinforced polymer is a common solution for strengthening and rehabilitating the existing structures. However, the concerning also raised a bout the effect of different environment to the durability of FRP composite system and its bonding performance to concrete substrate. In this paper, the deterioration strength of concrete beam strengthened with glass fiber-reinforced polymer (CBF) and glass fiber-reinforced polymer composite laminate (FC) after being exposed with outdoor, under submersion and wet-dry cycle condition with water, sea-liked water and sodium sulfate solution with a duration of 1000h, 2000h, 3000h, 5000h and 10000h were observed. The microscope also used to examine the physical changes of the external and rupture surface of the FC specimens. The results showed that the wet-dry cycle and submersion in water were associated with swelling and cracking of epoxy resin on FC and could shift the failure mechanism of the bonding interface of FRP-concrete. Submersion in sea-liked water and Na₂SO₄ caused considerable degradation of concrete strength while the GFRP composite seems to protect the concrete substrate from these solubles diffusions. The initiation of the spalling of resin was observed on specimens exposed to these solution.However, the capacity strength of all specimens is still higher than the controlled specimen but decrease gradualy if compare with specimens at the initial exposure duration.