Optimization of Coconut Fiber in Coconut Shell Concrete and Its Mechanical and Bond Properties

Abstract

Coconut shell concrete is one of the recently established lightweight concretes. This paper discusses the optimization of adding coconut fibers in both coconut shell concrete and conventional concrete. Coconut fibers at different aspect ratios of 16.67, 33.33, 50, 66.67, 83.33, and 100 and volume fractions of 1, 2, 3, 4, and 5% were tried. The maximum compressive strength was attained at an aspect ratio of 83.33 and volume fraction of 3% for conventional concrete, and aspect ratio 66.67 and volume fraction 3% for coconut shell concrete. Flexural strength increased by 30.63% (conventional concrete) and 53.66% (coconut shell concrete) on the addition of coconut fibers. Similarly, the split tensile strength increased by 19.44% and 30%, respectively. The number of blows needed for failure of specimen in impact resistance test was more for concrete mixed with fibers. The experimental bond stresses were higher than the theoretical values recommended by IS 456: 2000 (Indian Standard) and BS 8110 (British Standard). This study shows that the addition of coconut fiber enhances the properties of both conventional and coconut shell concrete.

Flexural Properties of Renewable Coir Fiber Reinforced Magnesium Phosphate Cement, Considering Fiber Length

“…Reis et al [ 9 ] found that coconut fiber reinforced concrete (CFRC) had greater flexural strength than other natural fiber reinforced concrete. Sekar et al [ 10 ] found that the flexural strength of concrete was obviously improved by adding coir fiber (CF), and the flexural strength increased with curing age increasing. A study conducted by Thanushan et al [ 11 ] demonstrated that CF could greatly improve the residual strength, ductility, flexural toughness, and energy absorption of earth cement blocks.…”

Influence of alkaline modification on selected properties of banana fiber paperbricks

“…The curing process is an important process employed in concrete development towards strength improvement 14 . Investigations carried out by 15 , 16 revealed an enhancement of strength from 7 to 28 days of curing. Correspondingly, reports were recorded in 17 , 18 and the endpoint is the heightening of strength with curing age.…”

Study on Durability Properties of Coconut Shell Concrete with Coconut Fiber

“…For comparison, 12.5 mm of conventional crushed stone aggregate was used in the production of CC. Since in an earlier study, the mechanical and bond properties were studied for the optimized aspect ratio and volume fractions with the selected mix proportions of both CC and CSC [11], the same mix proportions with the same optimized aspect ratio and the volume fractions were considered in this study. That is, mix proportion used for CC was 1:2.22:3.66:0.55 with a cement content of 320 kg/m 3 , and for CSC, it was 1:1.47:0.65:0.42 with a cement content of 510 kg/m 3 .…”

“…That is, mix proportion used for CC was 1:2.22:3.66:0.55 with a cement content of 320 kg/m 3 , and for CSC, it was 1:1.47:0.65:0.42 with a cement content of 510 kg/m 3 . Coconut fiber, having an optimum aspect ratio of 83.33 and a volume fraction of 3%, was was used in CC mix proportion in this study following [11]. Similarly, coconut fiber having an optimum aspect ratio of 66.67 and volume fraction of 3% was used in CSC mix proportion.…”

“…Coconut shell concrete (CSC) also exhibits the deficiency of weak tension. Therefore, to overcome the same in CSC, coconut fibers were introduced and the aspect ratio and volume fractions were optimized in an earlier study and were compared with CC with coconut fibers [11]. Fresh and hardened concretes with and without coconut fibers were tested for flexural strength, split tensile strength, impact resistance and bond properties for the optimized aspect ratio and volume fraction.…”