PURPOSES : Recently, air pollution caused by particulate matter has been worsening. Among the substances generating particulate matter, NOx is the main precursor of particulate matter and is widely distributed in areas with a high volume of traffic. TiO2 has been used as a material for removing NOx through a chemical reaction as a photocatalyst. In this context, the reduction of NOx through TiO2 concrete is proposed. However, the research on the surface deterioration on the performance of TiO2 concrete is not documented yet. Therefore, the objective of this study was to evaluate the long-term durability and NOx removal efficiency of TiO2 concrete by considering the concrete surface deterioration. METHODS : Freezing–thawing resistance test (KS F 2456) and scaling test (ASTM C 672) were performed to investigate the variation in the TiO2 penetration distribution and NOx removal efficiency of TiO2 concrete corresponding to surface deterioration. The long-term durability of TiO2 concrete was evaluated through an environmental resistance test and changes in TiO2 penetration depth and distribution characteristics. In addition, the NOx removal efficiency of TiO2 concrete was evaluated as surface deterioration occurs. RESULTS : As a result of the freeze–thawing resistance test, a relative dynamic elastic modulus of more than 80 % was detected. In addition, a TiO2 penetration depth of 0.3 mm, NOx removal efficiency of 11.2 %, and a 30 % of TiO2 surface prediction mass ratio were achieved after 300 cycles. As a result of visual observation of the scaling test, “0, no scaling” was secured. After 50 cycles of scaling test, the TiO2 penetration depth, NOx removal efficiency, and TiO2 surface prediction mass ratio were 0.3 mm, 36.3 %, and 63 %, respectively. Through the results of the environmental resistance test, the excellent long-term durability and NOx removal efficiency of TiO2 concrete were confirmed. CONCLUSIONS : As a result of the experiment, long-term durability and NOx removal efficiency of TiO2 concrete were secured. The application of TiO2 concrete can be a good alternative with long-term performance and durability.

본 연구에서는 염화물이 함유된 동결수에 의한 콘크리트의 내동해성을 검토하기 위하여 동결융해 및 표면스케일링 저항성을 평가하고자 하였으며, 이를 위한 배합으로서 물결합재비는 0.37, 0.42, 0.47의 3수준, 결합재 방식은 일반 OPC 콘크리트, 고로슬래그 미분말 50%의 2성분계 콘크리트 및 플라이애시 15%와 고로슬래그 미분말 35%의 3성분계 콘크리트로 설정하였다. 그 결과, 고로슬래그 미분말 50% 및 플라이애시 15%와 고로슬래그 미분말 35%의 혼합 시멘트계 콘크리트의 경우 일반 OPC 콘크리트에 비하여 동결융해 및 표면스케일링 저항성이 상대적으로 우수하게 나타났으며, 이를 통해 내구성 저하가 우려되는 해양 환경 하에서 비래염분 및 비말 등의 해수의 작용에 의한 콘크리트의 내구성 저하현상을 억제하기 위한 방안으로서 슬래그의 활용이 유효함을 확인할 수 있었다.