Coconut Shell Research Paper

2.3 Coconut Shell as Coarse Aggregates

2.3.1 Physical Properties of Coconut Shell

The physical properties of the coconut shell are vital in predicting what will be its effect when mixed with concrete. A study about using waste coconut shell as substitute for coarse aggregates in lightweight concrete was conducted by De Costa, Dasanayaka, Tantirimudalige, Udamulla and Ekneligoda (2017) that compares the physical properties of coconut shell to the conventional coarse aggregate (Granite).

Table 2 3 : Coconut Shell Properties by De Costa et al.

Physical Properties Coarse Aggregates Coconut Shell

Moisture content dry (%) 0.14 12.93

Moisture content wet (% 0.14 11.45

Specific Gravity 2.75 1.31

Water Absorption (%) 0.49 26.05

It is noticeable that

The addition of coconut fiber decreases again the strength of concrete with coconut shell, 46% to 55% of the compressive strength and 60% to 71% of the tensile strength of conventional concrete were only attained. The decrease in the mechanical properties of the concrete was opposed to the expected increase in strength when fiber was included. The decreased may be due to the fixed percentage of 3% that is greater than the optimum percentage of additional fiber of 0.5% to 2.0% that was discussed earlier in the previous

These signals include secondary electrons that produce SEM images, backscattered electrons, diffracted backscattered electrons that are used to determine crystal structures and orientations of minerals, photons which are used for elemental analysis and continuum X-rays, visible light and heat. Secondary electrons and backscattered electrons are commonly used for imaging samples: secondary electrons are most valuable for showing morphology and topography on samples and backscattered electrons are most valuable for illustrating contrasts in composition in multiphase samples. SEM analysis is considered to be non-destructive and X-rays generated by electron interactions do not lead to volume loss of the sample, so it is possible to analyze the same materials