Efficient healing of existed cracks in cement via synergistic effects of cement matrix activation and monomer polymerization

•The efficient healing of existing cracks is achieved by the synergistic reaction of cement matrix activation and organic polymerization of sodium acrylate (ANa).•ANa polymerization was systematically investigated for its effect on stimulated calcium silicate hydrate (C-S-H) and true healing systems.•The compressive strength of the specimens significantly improved, and the micro-cracks were completely sealed after 7-day curing. The composition and microstructure of the healed area were conducted.