The Potential of Rice Husk Ash (Rha) and Coconut Fiber (Cf) as Partial Replacement of Cement

Concrete is one of the significant element uses. in the field of construction. Through environment concern, the studies of recycling and utilizing the agricultural or industrial wastes material to be used in a concrete as replacement or admixtures has been established. This study is focusing on the utilization of rice husk ash (RHA) together with a coconut fiber (CF) as partial cement replacement of concrete. The purpose is to determine the strength and durability of concrete grade 30 when the combination of RHA and CF takes place in producing concrete. Coir has partially replace the cement weight by 1%, 2%, 3% and 4% while RHA replace the cement by 9%, 18%, 27% and 36% of the cement weight. The strength and durability will only be test after 7 and 28 days of curing. The composition of 1% of coconut fiber and 9% of RHA gives the maximum compressive strength in 7 days which is 38.12 N/mm2. The rate of water absorption for concrete is increase with the increment of percentage of coconut fiber and RHA content. At 7 days, the increment rate of water absorption was 1.56%, 2.11%, 7.31% and 10.33%, while at 28 days the increment rate ware 1.52%, 1.85%, 6.54% and 9.91% both for the 10%, 20%, 30% and 40% cement replacement respectively. The water absorption rate for 7 and 28 days are 2.95% and 2.18% respectively.