Experimental Behavior of Hollow Non-Prismatic Reinforced Concrete Beams Retrofit With CFRP Sheets.

Abstract

This study deal with five reinforced concrete non-prismatic beams hollows section retrofit with carbon fiber reinforced polymer (CFRP) under two point loads. These beams of dimension (length 1170 x height 260 x width 150mm) with different section (i.e. solid or hollow of two shapes) are investigated to evaluated the behavior at experimental test and to get capacity of beams retrofit with CFRP that similar to capacity of solid sections. The end support to provide all beams as simply supported. The four of R.C. beams are retrofit with CFRP strip (Sika CarboDurS512) and design to test up to failure. Also, it's have been explain the effect of Parameters which includes the effect of section (solid or hollow), hollow opening (shapes and materials) and effect of retrofitting with CFRP. Non prismatic beam with recess along length compared with non prismatic solid beam results show decreased in stiffness and an increased in the beam deflection by about (53% and 40% respectively). The square hollows are provided by steel pipe led to increased in load capacity and decrease in corresponding deflection compared with other materials (i.e PVC) by about (56%,33%), also the retrofit of beams by CFRP contributed to again in load capacity by about (27%) . Finally the comparisons between all beams are base on load carrying capacity, deflection, and crack pattern, strain of concrete and mode of failures.