抄録
In recent years when the quality of many concrete structures is progressively deteriorating due to carbonation, chloride damage, etc., various repair methods are being applied to prolong the life of public structures. Among these methods, the concrete surface coating method, where a material is applied over the surface to prevent substances from invading and deteriorating the concrete, has a long history, more than a quarter of a century. Many new protection techniques based on this method are being proposed even today. On the other hand, the adhesive ability of the concrete surface coating method has been one of the most important evaluation items for measuring the durability of coatings, and the measurement of adhesive strength in the single vertical axial direction has been mainly used for this evaluation. However, this test method has difficulties meeting our original purpose of comparing the adhesion performance between samples, because the test tends to often produce the same result: substrate destruction. Taking the above circumstances into account, another evaluation method that images the peeling-off of the coating films, i.e., the peel-off resistance measurement, was introduced. This method enabled us to observe clear differences between samples where the concrete substrates had been damaged by the adhesion strength measurement. In addition, some of the concrete surface coating methods showed a phenomenon that appeared at the peeled-off or damaged part of samples and varied in quality over time. From a series of concrete surface coating tests using both evaluation methods, we drew the conclusion that we could make clear the adhesion of coating films in a more practical and accurate way.
