Behavior of Continuous Steel-Concrete Composite Beams Reinforced with CFRP sheets

Abstract

The improvement in the flexural behavior of continuous steel-concrete composite beams is evaluated after adding carbon-fiber-reinforced polymers (CFRP) laminates to the concrete surface at the hogging moment regions. In this paper, an experimental program consists of three specimens tested in an inverted position under four-point loading is carried out to simulate a part of continuous steel-concrete composite beams at the hogging moment region. The experimental findings are used to develop and validate a reliable finite element (FE) model to simulate the nonlinear flexural performance of strengthened beams as well as plain beams. However, CFRP laminates enhance the beam capacity, a reduction in the beam ductility occurs and causes a limitation in the moment redistribution at the hogging moment regions Moreover, adding more layers of CFRP laminates leads to higher values of the beam stiffness and capacity but more reductions in ductility will occur. As the longitudinal steel rebars ratio increases, the contribution of CFRP laminates to enhance the beam capacity is diminished. Also, applying CFRP laminates through the full length of the hogging moment region helps to reduce the creation of fatigue cracks in the steel rebars.