Flexural strengthening of concrete beams with EB-FRP, SRP and SRCM: Experimental investigation

Innovative composite materials for flexural strengthening of concrete structural members have been recently proposed by construction market. They are able to overcome some issues related to traditional composite material, such as high cost and fire resistance. They include composite materials made of different types of organic matrix (i.e., cement-based mortar and pozzolan-reaction cementitious mortar) and reinforcement (i.e., steel fibre fabric). An experimental investigation has been carried out on prestressed-concrete beams strengthened in flexure with traditional (i.e., pultruded carbon laminate bonded with epoxy resin) and different innovative composite externally bonded systems (i.e., steel fabrics glued with different types of adhesive) in order to compare their structural performance between them and with respect to unstrengthened specimens. At this aim, a total of fifteen specimens characterized by an overall length of 2400 mm and cross-sectional dimensions of 120 by 140 mm were subjected to four-point-bending tests. Test results highlighted the high potential of the innovative composite systems for flexural strengthening applications and similar effectiveness compared with the pultruded carbon laminates. The recorded response of the specimens is presented and discussed and the measured strength and deflection of the specimens are estimated. Comparison between theoretical prediction and experimental results shows a good agreement.