Quantitative Crack Pattern Analysis for Understanding the Mechanical Degradation of ASR-Affected Concrete with Different Reactive Aggregate Sizes

This study aims to investigate the relationship between mechanical property degradation and expansion through quantitative crack morphology analysis in ASR-affected concrete. Three groups of specimens with different reactive aggregate sizes were prepared and subjected to the alkali-silica reaction (ASR) acceleration. The expansion of each specimen was continuously measured, and tests were conducted to observe the compression behavior and crack patterns exhibited by the specimens at different levels of expansion. The specimens were sliced and subsequently embedded into fluorescent resin, and crack images were captured using a digital camera under ultraviolet light. Image analysis techniques were employed to obtain quantitative information regarding the crack size, including length and width distributions. The experimental results revealed that larger cracks resulted in a higher compressive strength reduction than smaller cracks. Furthermore, we demonstrated that there is a strong correlation between the compressive strength and expansion when considering the crack size distribution. This research paves the way for future models to better predict the mechanical behavior of concrete structures under ASR deterioration.