In this research, the application of repair methods of water leakage cracks using self-healing technologies for subway tunnels is presented. In order to apply crack self-healing water stop agents and quick setting agents in subway tunnels, laboratory and field tests were performed based on various previous researches. Especially, this study focused on development of crack repair materials and their new repair methods. Therefore, various repair materials were examined for new repair materials with self-healing capability applied to crack sealing method and to patching repair method. The results show that the proposed water leak repair methods using water stop agent, quick setting agent and patching materials using self-healing ingredient were effective under the subway tunnel conditions. It is preferable in water leak repair to add self-healing components to sealers and water stop agents.

It is important to doubt common knowledge established in the past when we face difficulty to seek further development based on them. In this presentation the importance of doubting common knowledge is pointed out for further endless development of the field of study by discussing stagnation of chloride ion ingress and liquid water penetration into concrete, stagnation of water pass through a crack in concrete and the inconsistency between Carbonation depth and cover concrete spalling risk.