Experimental study of the bond interaction between CFRP and concrete under blast loading

Abstract

Specific to blast loading, bond shear tests between carbon fiber reinforced polymer (CFRP) strips and concrete have not yet been reported in literature, to the best knowledge of the authors. Given the high potential of strengthening concrete with CFRP to increase blast resistance, it is necessary to better understand the dynamic interaction between concrete and CFRP under blast impulse. This article presents a new experimental setup developed in order to study blast driven bond interaction between CFRP and concrete. An evaluation of the bond at the interface between the CFRP strip and the concrete is conducted in order to identify the parameters that affect the bond strength under blast loading. Several retrofitted specimens with different bond strength are tested. An explosive driven shock tube (EDST) set-up is used to generate the blast loading. Piezo resistive strain gauges and digital image correlation (DIC) measurement are used to record the debonding process and the evolution of the strain along the bonded area. As such, the bond behaviour is studied for three different bond lengths and the effect of interaction of the blast wave within the concrete is highlighted. The experimental tests demonstrate that under blast loading, the debonding between the CFRP strip and the concrete occurs due to a combined effect: interface stresses caused by the induced force in the CFRP and additional stresses resulting from the propagation of the blast induced stress wave within the concrete.

Experimental study on SHPB cyclic impact of rubber-cement composite with different confine modes

“…However, rubber concrete still has a long way to go in practical application because the low strength and fatigue damage accumulation of rubber-cement composites under cyclic impact can not be used as the main bearing structure and key components under frequent dynamic disturbance. Due to the superior mechanical properties of fiber-reinforced polymer (FRP) and steel cylinder/steel tube materials, FRP and steel cylinder/steel tube are widely used as reinforcement materials in civil engineering [11,12]. Researchers have also done a lot of research work on the dynamic mechanical properties and dynamic response characteristics of carbon fiber-reinforced polymer (CFRP) and steel cylinder/steel tube reinforced concrete materials.…”

“…Researchers have also done a lot of research work on the dynamic mechanical properties and dynamic response characteristics of carbon fiber-reinforced polymer (CFRP) and steel cylinder/steel tube reinforced concrete materials. Maazoun et al [11] studied the bond interaction mechanism between CFRP and concrete under explosive loading and determined the parameters that affect the bond strength between CFRP and concrete under explosive loading. Xiong et al [13] used the SHPB test system to study the high strain rate compression behav-ior of CFRP-confined concrete.…”

Finite element modelling of RC slabs retrofitted with CFRP strips under blast loading

“…They found that the interfacial fracture energy, bond strength, and interfacial bond shear stress-slip are sensitive to strain rate. For blast loading, Maazoun et al [15] developed a double novel blast bond shear test set-up where the effect of propagation of the blast wave within the concrete is highlighted using digital image correlation (DIC) measurement. The experimental tests demonstrate that under blast loading, the debonding between the CFRP strip and the concrete occurs due to a combined effect: interface stresses caused by the induced force in the CFRP and additional stresses resulting from the propagation of the blast induced stress wave within the concrete.…”