Effect of crack patterns induced by different accelerated temperature on mechanical behavior of ASR-damaged concrete

Crack pattern induced by alkali-silica reaction (ASR) varies depending on environmental conditions, which affects the mechanical properties of concrete.This study aims to investigate the change in mechanical behaviors of ASR-damaged concrete with respect to acceleration temperature and crack pattern.Cylinder specimens were fabricated and immersed in 1 mol/L NaOH solution at two different temperatures, 40 and 60, for ASR acceleration until the expansions reached 0.25% and 0.50%.Subsequently, a cyclic compression test was performed to identify the elasticity and plasticity as well as the compressive strength and elastic modulus.In addition, using fluorescence epoxy-impregnated samples in each specimen, crack patterns due to ASR were observed under ultra-violet (UV) light and quantitatively analyzed through image analysis.The expansion rate of concrete stored at 60 was higher than that at 40, depending on which different ASR crack pattern and elastic modulus appeared.Large cracks were more prevalent in the specimen immersed at 40 than that at 60, and the reduction in elastic modulus of the specimen immersed at 60 was less than that at 40.The fracture parameters representing the remaining shear elasticity were calculated based on the measured elastic and plastic strains, and the results indicated that the fracture parameter of the specimen immersed at 40 was slightly lower than that at 60.