DUCTILITY OF HYBRID FIBER REINFORCED CONCRETE

摘要

The cementitious materials are inherently tension-weak and brittle. The inclusion of closely-spaced fibers into the cement-based matrix has been demonstrated to effectively overcome such drawbacks. The concept of hybridization has been popularized in the past few years in the fiber reinforced composites since the hybrid system possesses certain characteristics of more interest in civil engineering. This paper is aimed at investigating the effect of the hybrid fibers on the ductility of cement-based composites under compression. Three steel fibers with different geometry, i. e. hooked, crimped, and deformed, as well as carbon fibers are used in this study. Furthermore, attempt is made to understand the influence of various factors on the ductility of fibrous composites, including the aspect ratio and geometry of the steel fiber, the total volume fraction of fibers and the proportion of steel fiber content to carbon fiber content. It was found that each of the presented variables had a significant influence on the ductility performance of the hybrid composites. In addition, comparison is performed between the hybrid fiber reinforced composite, and that reinforced with steel fibers alone, the results of which, showed that the hybrid fiber system can yield more pronounced enhancement in ductility than the sole fiber reinforced system. Apart from that, the effect of the fiber distribution fashion was examined with respect to mono steel fiber system, including the horizontally aligned fiber reinforced composites and randomly dispersed fiber reinforced ones. The experimental response exhibits the horizontally distributed fibers are more effective in improving the ductility.