Experimental study on low-strength concrete joint core strengthened with steel meshes for connecting PFCC column and RC beam

Abstract

This paper presented a new joint core strengthened with multi-layer steel meshes for connecting the PVC-FRP Confined Concrete (PFCC) column and Reinforce Concrete (RC) beam. Seven specimens were tested under concentric compression and the effects of several parameters including the height, diameter of specimen and volume ratio of steel mesh on the compressive behaviors were investigated. Test results showed that all the reinforcement yielded successively and eventually the crushing of the concrete dominated the failures of specimens. The ultimate bearing capacity and ultimate equivalent axial strain decreased as the height of specimen increased, while they increased as the diameter of specimen or the volume ratio of steel mesh increased. The ultimate strains of all the reinforcement and concrete increased as the height of specimen increased while they decreased as the diameter of specimen or the volume ratio of steel mesh increased. Considering the influence of height of specimen, a modified formula for conveniently predicting the ultimate bearing capacity of the joint core strengthened with steel meshes was proposed based on the theory of confined concrete and superposition principle of multiple confinement. The predicted results were in good agreement with the experimental data. Additionally, an equivalent stress–strain relationship model of the joint core strengthened with steel meshes was suggested based on the experimental research. The predicted curves agreed well with the measured equivalent stress–strain curves. Moreover, a validated Finite Element (FE) model for the joint core strengthened with steel meshes was developed to conduct parametric studies, which broadened the available experimental results about the mechanical performances of the joint.

Shear capacity estimation of core steel tube reinforced PCCC column-beam interior joint under quasi-static load

“…However, PCCC column-beam interior joints present unsatisfactory fire resistance and need to be further improved. From the perspective of locally enhanced joint core region, the steel mesh joint (Yu F et al, 2020), enlarged ring beam joint (Bu SS et al, 2020) and core steel tube (CST) joint (Yu F et al, 2020), were proposed for the connection between PCCC columns and RC beams. Subsequently, the author’s research group carried out a systematic study on PCCC column-enlarged ring beam joints, including axial compression (Yu F et al, 2019), eccentric compression (Yu F, Feng CC et al, 2020), and seismic behaviors (Song ZK et al, 2021).…”

“…From the perspective of locally enhanced joint core region, the steel mesh joint (Yu F et al, 2020), enlarged ring beam joint (Bu SS et al, 2020) and core steel tube (CST) joint (Yu F et al, 2020), were proposed for the connection between PCCC columns and RC beams. Subsequently, the author’s research group carried out a systematic study on PCCC column-enlarged ring beam joints, including axial compression (Yu F et al, 2019), eccentric compression (Yu F, Feng CC et al, 2020), and seismic behaviors (Song ZK et al, 2021). The enlarged ring beam joint exhibited the advantages of convenient connection with RC beam in different directions, high bearing capacity and considerable seismic performances, which provided an effective connection mode for PCCC structures.…”

Efficacy and Damage Diagnosis of Reinforced Concrete Columns and Joints Strengthened with FRP Ropes Using Piezoelectric Transducers

“…Dalfre and Barros [ 15 ] reported successful NSM techniques for the strengthening of slabs, too. Other forms of materials and techniques, like fully-fastened-haunches [ 16 ], steel meshes [ 17 ], external bars [ 18 ], and steel plates with shear connectors [ 19 ], have also been experimentally investigated for the upgrading of RC elements and BCJs. Analytical efforts have also been reported, as well [ 20 , 21 ].…”

Influence of Carbon Fiber-Reinforced Ropes Applied as External Diagonal Reinforcement on the Shear Deformation of RC Joints

“…A state-ofthe-art report for near surface mounted FRPs has also been published [17]. Strengthening techniques using steel products mounted on the surface of concrete elements have also been reported [18][19][20][21]. Further, analytical approaches have been proposed, too [22,23].…”