2025 Volume 78 Issue 1 Pages 356-364
The purpose of this study is to investigate the effect of the application techniques of polymer-modified mortars（PCM）on its flexural, compressive and adhesive strengths in the patching work for the reinforced concrete structure. The specimens for those strength tests are prepared by using PCMs at the set aside time after the mixing of 0, 30 and 60 min with or without remixing. The specimens for adhesive strength test of PCM to base concrete are also prepared at 1, 6 and 24 h after treating the surface of the base concrete by water-absorption-controlling material（WACM）, and at the WACM treating surface having the dry to the touch given by different conditions. As a result, the effect of the set aside time on the flexural and compressive strengths of PCM is hardly recognized. The adhesive strength of PCM to the base concrete is decreased with an elapse the set aside time. However, the effect of the remixing of PCM after the set aside time on those strengths is hardly recognized. The adhesive strength of PCM to the base concrete is decreased with an elapse the time after WACM treating for the surface of the concrete. The higher adhesive strength is given for the specimen prepared by 1h after the WACM treating the surface of the concrete having the dry to the touch. The effects of the conditions to give the dry to the touch of WACM treating concrete surface on the adhesive strength of PCM to the concrete is not recognized.
