Failure patterns and mechanical behavior of the cement mortar column partially confined by the FRP jacket

Abstract

Fiber-reinforced polymer (FRP) composite has been recently adopted to maintain the integrity of infrastructure made of cement mortar, attributed to its high strength-to-weight ratio and easy-to-construct. To obtain an in-depth understanding about the compressive behavior of cement mortar samples with variable FRP center wrapping heights, both the acoustic emission (AE) response and deformation characteristics of which were comprehensively investigated in the present research. The relationship between the confinement provided the exterior FRP jacket and the mechanical characteristic was also explored, followed by the economic analysis on this reinforced technique. Test results indicated that both the deformation ability and the load-bearing capacity gradually increased with the increased center wrapping height of the FRP jacket. When the larger the AE energy generated at the initial compression stage, the more dispersed AE localization. Meanwhile, these main cracks occurred on the surface of reinforced cement mortar generally transformed from the FRP wrapping strip towards other extremities. Correspondingly, the number of tensile cracks of FRP partially wrapped cement mortar decreased with the increased axial deformation. Note that the residual integrity of these reinforced cement mortar with larger FRP-center wrapping height is much superior than its counterparts. The force state of partially reinforced cement mortar with FRP confinement was also discussed in the present research and the results of which were compared with existing theoretical models. Compared to other theoretical models, Teng's model shows the most accuracy in predicting the mechanical behavior of FRP partially reinforced cement mortar.