TITLE:
Optimization of the Structural Properties of RHA-Concrete Using Osadebe’s Mathematical Program
AUTHORS:
Godwin A. Akeke
KEYWORDS:
Compression, Flexure, Tension, Optimization, Pozzolans
JOURNAL NAME:
Engineering,
Vol.15 No.7,
July
31,
2023
ABSTRACT: This research work focused on the analyses of the
compressive strength, modulus of rupture and elasticity
of RHA-concrete that was gathered from four states in Nigeria (Cross River,
Ebonyi, Enugu, and Benue). The results were calculated and compared
geographically by using Osadebe’s mathematical
program. They had corresponding relative silica values of 85, 75, 1, 65, 2, and
60.1. In place of cement, RHA was utilized in concrete at different percentages
of replacement in the concrete. The results showed that strength values
increased as RHA replacement increased by 5% - 15% and decreased as the
percentages of RHA in the concrete increased. When RHA is utilized to
partially replace cement in concrete, the strength is improved. RHA is a yearly
supply of silica and a naturally occurring pozzolan. The Compressive strength
values varied between 37 and 42 N/mm2. The elastic modulus of a
short cylinder obtained was between 3.15 and 3.7 N/mm2. It was
discovered that the rupture modulus ranged from 0.6 to 4.2 N/mm2.
Mathematical prediction models employing Osadebe’s method were created. The
findings confirmed that there were differentials in the
results and laboratory responses of RHA concrete based on spatial properties,
Fisher’s statistical tool was used to confirm the adequacy of the model and the
mean values, variance and critical values were found satisfactory for the 10
observation points.