Strengthening of structures is a major concern for researchers in the civil engineering community in recent years due to the aging of these structures and the need for effective methods of strengthening.
Steel structures such as buildings, bridges, offshore structures are exposed to deterioration due to a wide variety of reasons such as design errors, lack of proper maintenance, fatigue damage, steady increase in the weight of highway vehicles, increase in traffic density and the increase of the applied forces due to earthquakes or by environmental factors such as the problem of corrosion.
The objective of this research is to determine the efficiency of using CFRP strips as web reinforcement to increase the shear strength of steel I-beams. This thesis studies a new technique to strengthen the steel I-beam by using the CFRP strips diagonally on the web as shear reinforcement. The study also discuss the effectiveness of using different positions of CFRP strips on the web by applying CFRP strips on one side or both sides of the web. The effectiveness of CFRP strips thickness by using two layers of CFRP strips on each side of the web is also investigated in this study.
Several real-size models of steel I-beams with different strengthening schemes were tested experimentally under two concentrated loads and finite element analysis by using ANSYS. Parameters to be covered include load bearing capacity, shear strain on the steel beams, strain on the CFRP strips and vertical deflection at mid-span.