Effects of fibers length on the properties of kenaf fibers- reinforced geopolymer concrete

Abstract

As a material for sustainable development, geopolymer concrete (GPC) obtained great research interest. However, it displays brittle behavior with low tensile strength, fracture toughness, and ductility identical to ordinary Portland cement (OPC). The use of short discrete fibers is an effective way to overcome such weaknesses. This paper studies the effects of fibers lengths on the properties of geopolymer concrete containing kenaf fibers (GPCKF). Three lengths of 20 mm, 30 mm, and 40 mm were selected. Besides the fresh properties, the mechanical properties of the mixes are evaluated through compression, tensile and flexural tests. The findings showed that the increase in kenaf fibers length resulted in a significant improvement in flexural and tensile strength. On the contrary, the workability and compressive strength are decreasing. The optimum length of kenaf fibers is 30 mm that improved the tensile and flexural strength by 6.71% and 25.90%, respectively compared to the plain GPC. Through these findings, the performance of GPCKF is known, and more exploration of its usage can be carried out by the industry.