Study on the micro-mechanism and structure of unsaturated polyester resin modified concrete for bridge deck pavement

Abstract To solve the problems of durability reduction and service-life shortening of bridge deck pavement concrete, this study investigated the effect of unsaturated polyester resin (UPR) as a modifier on the cement hydration and the microstructure morphology of pore, crack and interface transition zone (ITZ) of cement concrete. The enhancement mechanism of UPR incorporation into bridge deck pavement concrete was determined with the aid of meso- and micro-structure analysis technology and digital image processing approach. The results indicated that the incorporation of UPR-emulsion might have a significant retarding effect on the cement hydration process while greatly enhanced the compactness and anti-permeability of the concrete. In addition, the addition of UPR emulsion could effectively delay crack initiation and restrain the propagation of crack during consolidation process, and reduce the zone area and materialize intense densification and homogenization in terms of ITZ. In comprehensive consideration of the characteristics of pore structure and micro-crack, the introduction of 3% UPR-emulsion could be recommended to achieve the performance reinforcement of deck pavement concrete to a certain degree.