Abstract
Most of repair works have been carried out with trowel, using polymer-modified mortar (PCM). In this research, a new method of patching with wet spraying application using set-accelerating agent and PCM was developed. As for newly developed PCM, quality control is possible simply with SL-flow test. Spraying the back side of the steel bar together with air blow can fill up certainly. There is little difference in pore size distribution between PCM with the set-accelerating agent and PCM without this agent. PCM has high durability and bond strength. Spalling-off resistance become high by using the fiber in the part of cover. In order to make the patching of high quality on site, training system of nozzle-work is developed too. This patching method was applied to the repair construction of Subway and Railroad Bridge.
