Performance evaluation of rapid-set prepackaged cementitious materials for rehabilitation of surface

摘要

This paper summarizes the findings of an extensive research project that aims to identify the successes and potential problems of 23 rapid-set prepackaged cementitious materials available on the market. The results of this study are anticipated to provide potential users with reliable information for deciding which materials have the greatest potential for desirable performance. It was found that most rapid-set prepackaged materials in this study demonstrated rapid setting, fast strength development, low permeability, and acceptable bonding capacity. However, the lack of resistance to freezing and thawing and the high sensitivity to restrained shrinkage cracking were likely to cause premature deteriorations. Research findings also indicated that although magnesium phosphate cementa??based materials set and developed strength extremely quickly and shrank negligibly, their high permeability and poor durability made them unsuitable for long-lasting repairs. In contrast, some materials exhibited normal setting and strength development similar to what was observed in conventional Type III portland cementa??based concrete. The main concerns for these materials were, again, poor resistance to freezing and thawing and high risk of shrinkage cracking. In rare cases, materials showed poor early-age or late-age strength, making them inadequate for repair of concrete transportation structures.