MECHANICAL PROPERTIES OF SUSTAINABLE FIBER-REINFORCED LIGHTWEIGHT AGGREGATE CONCRET

Abstract

With the rapid growth of high-rise buildings and large-scale structures, there is a need to preserve natural resources and reduce loads on buildings by using lightweight concrete to achieve better performance for structures. In the study, four groups were prepared; the first group included one mix containing natural aggregate, and the second mix replaced all the natural aggregates with lightweight pumice aggregates. These mixes are reinforced with carbon fiber with a 0.5% volume fraction. In the second group, a variable volume fraction of carbon fiber of (0.0 and 1%) of mixes. In the third group, the mixes have different lengths of carbon fiber (20mm, 30mm) and a volume fraction of carbon fibers 0.5%. Finally, the fourth group partially replaces sand as a variable with a percentage of lightweight fine aggregates (10% and 30%) reinforced with fibers. Adding carbon fibers to the concrete specimens by 0.5% and 1% improved splitting tensile strength and flexural strength compared to the specimens containing carbon fibers with a length of 5mm. Also, enhanced samples containing fibers by 0.5% and lengths of 20 mm or 30 mm, compared to the sample containing carbon fibers with a length of 5 mm. Also, the specimens containing lightweight fine aggregates as a replacement with a percentage of sand have a lower splitting tensile strength and flexural strength than the reference mix.