Enhancing the Durability of Concrete Dams Through Self-Healing: The Role of Superabsorbent Polymers and Crystalline Additives

Surface cracks in concrete can significantly reduce its durability. Controlling microcracks at an early stage can prevent their growth and formation of larger cracks. A promising solution is the incorporation of self-healing agents in concrete. This study evaluates the effects of superabsorbent polymers, crystalline additives, and fly ash on the self-healing capability of concrete. The self-healing process was evaluated using permeability tests on cracked specimens, while physical crack closure was analyzed through optical microscopy and geometric measurements. Cracks were monitored for healing over ۴۲ days. Results indicated that self-healing behavior varied with environmental conditions. Crystalline additives required water to activate, which was supplied by superabsorbent polymers, enhancing healing in dry and cyclic wetting and drying conditions. Specifically, superabsorbent polymers increased the healing rate by ۶۲% in dry conditions and ۳۲% in cyclic conditions compared to reference concrete. Fly ash had little effect on permeability reduction but reduced calcium carbonate precipitation on crack surfaces. Compression tests indicated that superabsorbent polymers reduced concrete strength by ۱۵%, though their combination with crystalline additives mitigated this reduction to only ۵%. Overall, the findings highlight the potential of self-healing concrete in improving the durability of dams under various environmental conditions.

کلیدواژه ها:

Self-healing concrete ، Durability ، Dam ، Crack closure ، Superabsorbent polymers