TITLE:
Size Variation of Palm Kernel Shells as Replacement of Coarse Aggregate for Lightweight Concrete Production
AUTHORS:
Humphrey Danso, Frank Appiah-Agyei
KEYWORDS:
Compressive Strength, Dry Density, Flexural Strength, Lightweight Concrete, Palm Kernel Shell
JOURNAL NAME:
Open Journal of Civil Engineering,
Vol.11 No.1,
March
30,
2021
ABSTRACT: The utilization
of palm kernel shells (PKS) as an alternative to conventional materials for construction
is desirable to promote sustainable development. The purpose of this study is
to investigate the properties of lightweight concrete produced with different
sizes of PKS of 6, 8, 10, 12 mm and mix (consisting of 25% each of the four
sizes). RPK sizes were used to replace coarse aggregate in the concrete and
cured for 7, 14, 21 and 28 days. The tests performed on the concrete are dry
density, compressive strength, flexural strength, EDS and SEM. It was revealed
that the densities of the concrete specimens were all less than 2000 kg/m3,
which implies that the PKS concrete satisfied the requirement of lightweight
concrete for structural application. The compressive strength of the 12 mm PKS
concrete specimens at 28-day of curing was 10.2 MPa which was 4% to 15.9%
better than the other PKS sizes concrete. The flexural strength of the 12 mm
PKS concrete specimens at 28-day of curing was 2.85 MPa which was also 3.2% to
57.07% better than the other PKS sizes concrete. It was also revealed by the
SEM analysis that there was a good bond between the palm kernel shells and the
mortar. A high calcium-silicate content was found in the concrete which
resulted in a Ca/Si ratio of 1.26 and Al/Si ratio of 0.11. The study therefore
concludes that size variations of PKS as replacement of coarse aggregate have an
influence on the properties of the lightweight concrete and recommends 12 mm
PKS for use by construction practitioners for lightweight concrete structural
application.