Evaluation of crack sealing efficiency using super absorbent polymer at concrete layer interfaces: a statistical approach

This study investigates the self-sealing capabilities of concrete enhanced with superabsorbent polymers (SAP) by employing a comprehensive statistical approach to assess crack-sealing efficiency at concrete layer interfaces. The experimental design includes varying SAP ratios (0.2% & 0.4%) and particle sizes (> 600 μm, 600–300 μm, and 300–150 μm), with samples subjected to different sealing mediums, such as water and calcium hydroxide solutions. Key statistical analyses, including empirical cumulative distribution function (CDF), probability plot analysis, and regression analysis. Results indicate a crack-closing ratio of up to 0.947 for SAP particles ≥ 600 μm in Ca (OH)₂ at a 0.4% SAP ratio, outperforming smaller particle sizes (300 − 150), which achieved only 0.64. In water, larger particles (≥ 600 μm) yielded a crack-closing ratio of 0.733, while smaller particles (300–150) reached 0.57. The 0.4% SAP ratio demonstrated greater consistency, as evidenced by lower standard deviations (0.131 in Ca (OH)₂, 0.155 in water) compared to the 0.2% ratio. The application of probability theory, employing Buffon’s needle and Poisson distribution, modeled the SAP-crack interaction, enhancing understanding of sealing probabilities based on SAP distribution within the concrete.