The Influence of the Curing Conditions on the Behavior of Jute Fibers Reinforced Concrete Cylinders

This paper presents an innovative method of reinforcement of concrete based on the use of the Jute fibers composites. These renewable raw bioresource fibers are available at a low cost. Moreover, they can be compared to Glass Fiber-Reinforced Polymer (GFRP) by enhancing the resistance of Jute Fiber-Reinforced Polymer (JFRP), while improving the compatibility between the fiber and the resin. For that purpose, this paper presents an experimental study that evaluates the influence of the curing conditions (time and temperature) on the behavior of JFRP laminates and concrete members strengthened by JFRP. The curing conditions at 30 °C for 2h 30min and at 50 °C for 1 h were the only two parameters studied and determined on the basis of Sikadur 330 properties and preliminary tests. Through the experimental tests, the maximum load capacity and observed failure modes are investigated. The results indicated that the curing at 30 °C for 2h 30min is the optimum curing condition. In addition, a low difference in the maximum load capacity was noted in the case of 50 °C. As to the failure modes, all the specimens cured with additional heat before being left under room conditions, have shown the ductile mode failure, especially in the case of specimens cured at 30 °C during 2h 30min. The analytical model conducted in this paper predicts the elastic modulus depending on temperature. The obtained results and proposed model can be used as input parameters in the analysis and design of externally strengthened members with Jute FRP composites.