79 / 2022-04-14 21:06:13

Experimental and numerical investigation of reinforced concrete beams strengthened with internal CFRP meshes in shear

CFRP mesh, Stirrup, SCC, Shear Capacity, Average Tensile Strain.

This study aims to develop a new method for shear reinforcing concrete beams by using the CFRP meshes as a replacement for conventional stirrups inside concrete cover. Seven self-compacting concrete (SCC) beams shear reinforced with CFRP meshes were tested along with one conventional SCC beam for reference to investigate their performance improvement, particularly in shear capacity. The experimental results highlighted that the failure modes of the tested beams were dominated with shear-compression failure in the shear/bending moment regions. In addition, the shear capacity and the shear carried by CFRP meshes significantly improved with a higher number of the internal mesh layers. However, the increasing ratio of shear capacity was not proportional to the shear reinforcing ratio. Furthermore, finite element analyses (FEA) based on ABAQUS/Standard software were conducted to provide analytical estimations of the shear behavior of the proposed SCC beams. It was observed that the average tensile strain of the internal CFRP meshes varies between 5000 and 9000με at ultimate state, which further clarified the efficiency of the proposed shear reinforcing method. Finally, an explicit calculation formula is developed based on nonlinear regression analysis (NRA). The analytical results revealed that the predicted values agree very well with the test data, which can effectively predict the shear capacity of SCC beams reinforced with internal CFRP meshes in shear.