BENDING AND SHEARING STRENGTH OF T-FORMED BEAM MADE OF STRUCTURAL LIGHT CONCRETE USING FRP SHEETS

To study enforcement effect of T-formed beams made of Structural lightweight concrete by binding CFRP with use of epoxy resin on the bending & shearing resistance, nine lab samples were designed, built and tested. These samples were divided into A, B & C groups, regarding their weakness. In all beams, two rods # 12 were used as compressive armature. In A, designing was such that beams have bending weakness. In these beams, two rods #12 were used as tensile armature and rod # 10 were used as shearing armature with a distance of 7.5 cm. In B, designing was such that beams have shearing weakness and 4 rods # 16 were used as tensile armature , the distance of stirrup was 30 cm. In c, designing was such that beams have shearing and also flexural weakness , In these beams , two rods # 12 were used as tensile armature and the distance of stirrups was 30 cm. According to observed studies, in flexural strengthening, beams have had a strength increase of 60%, although breaking was shearing and CFRP sheets didn’t reach the rupture stage. Studying beam’s shearing strengthening represents loading capacity increase of 20% and breaking was as stratified cutting of concrete with CFRP sheet. Also, we observed 45% increase of beam’s loading capacity from bending and also shearing strengthening together. In this case, failure mode was as stratified cutting of concrete with CFRP sheet from the beam’s side.

Keywords:

strengthening , tensile armature , CFRP , flexural