Experimental behavior of FRCM-confined concrete under high temperature

The paper investigates the behavior of concrete confined through FRCM (Fiber Reinforced Cementitious Matrix) composites subjected to high temperatures. Small scale cylindrical specimens (150x300 mm) were confined using two types of carbon fiber (dry and resin impregnated). For the sake of comparison two layers of FRCM were applied to all confined specimens. After curing, cylinders were exposed to four ranges of increasing temperatures being 20°C (ambient), 80°C, 100°C and 250°C and then tested under cyclic loading. The experimental results show that thermal stress significantly influences the confinement effectiveness of FRCM composites. Exposure to high temperatures reduces the ultimate confined strength and strain. For specimens confined with resin impregnated fibers, the observed stress-strain trend of confined elements tested after high temperatures exposure significantly differs from specimens tested under standard ambient conditions.