Abstract:Splitting testings on 48 100mm×100mm×100mm concrete specimens combined by two parts were conducted to figure out efficient methods to improve the interfacial bonding behavior between existing concrete and attached concrete during retrofitting. The attaching concrete was incorporated with 4 different kinds of fibers

which were stell fiber

polyacrylonitrile fiber

basalt fiber and carbon nano-tube. The effects on bonding behavior due to different fiber and proportion were investigated to find out the best one. It was showed that the bonding behavior was improved when the attaching concrete incorporated with fiber. Those incorporated with carbon nano-tube performed best

the following one was polyacrylonitrile fiber

and then basalt fiber and steel fiber in order. Furthermore

splitting testings on 192 extra specimens

in which the attaching parts were incorporated with fiber and styrene-acrylic emulsion

were carried out to study the interfacing bonding behavior. The effects due to different fibers

content of styrene-acrylic emulsion and proportion of fibers were evaluated according the testing results. Anyway

incorporating styrene-acrylic emulsion to the attached concrete generally showed better performance than those without styrene-acrylic emulsion. The best content proportion for both fibers and styrene-acrylic emulsion was pointed out according to the testing results.