Development of synthetic-coconut hybrid fiber reinforced mortar

• Main Author: Debbie Nur Allysa Mattius
• Format: Academic Exercise
• Language: English; English
• Published: 2022
• Subjects: TA401-492 Materials of engineering and construction. Mechanics of materials
• Online Access: https://eprints.ums.edu.my/id/eprint/35211/1/24%20PAGES.pdf; https://eprints.ums.edu.my/id/eprint/35211/2/FULTEXT.pdf; https://eprints.ums.edu.my/id/eprint/35211/

A cementitious composite is any composite that contains Portland cement as its principal binder, and it can take the shape of concrete, mortar, grout, and other materials depending on its composition. Despite having numerous advantages, one of the disadvantages of mortar is it has low tensile strength. The purpose of this research is to determine the variation of mechanical properties which are compressive, tensile, and flexural strengths of synthetic-coconut hybrid fiber reinforced mortar with crumb rubber with different mix design. This research was conducted on mortar that incorporated rubber crumb aggregate as replacement for sand at 5%, 10% and 15%. Rubber crumb aggregate is generally obtained from recycled tyre. Many research shows adding rubber crumbs will reduce the strength of mortar. Thus, fibers will be adopted as the reinforcement for the rubberized mortar. Combination of different types of fiber proven to perform better than mortar with single fiber. In this research, synthetic fiber which is Forta Ferro Fiber (polypropylene) and natural fibers which are coconut fiber will be combined. With the addition of rubber crumb aggregate and fibers, the flowability could be negatively affected. Therefore, superplasticizer which is High Range Water Reducing Admixture (HRWRA) will be used to improve the flowability while maintaining mortar strength. In this research, a total of 351 specimens were tested which consist of 13 different design mix with 27 specimens each. For each mix design, the specimens undergo compressive strength test, flexural strength test and split tensile strength at 3 days, 7 days and 28 days of curing. Main findings of this research shows that addition of hybrid fiber improves the mechanical properties of rubberized mortar.