Modification Analysis of Two Different Cement Grades and Their Impact on Vibrated Concrete Qualities

Abstract

This project investigated the effect of changing the cement grade on the properties of vibrated concrete. Various tests were conducted on the constituent materials: Dangote Portland cement of two grades (32.5N and 42.5R), rivers and crushed granite stones. Concrete was prepared to 1:2:4 non-vibrated concrete and 1:11/2:3 ratios for both vibrated and 60 concrete cubes of 150x150x150 mm³ were moulded and cured for 7, 14, 28, 35 and 56 days. Workability and compressive strength tests were conducted on wet and dry concrete. The results reveal that the consistency, initial and final setting time for 32.5 cement grade varies from that of 42.5N. The compressive strength of concrete increases as the age increases for both grades at 1:2:4 and 1:11/2:3 mix ratios. Also, concrete produced with a cement grade of 32.5N has a lower compressive strength than the 42.5 grade of both vibrated and non-vibrated concrete for both grades 1:2:4 and 1:1/2:3 mix ratios. Vibrated concrete produced a denser and higher compressive strength than non-vibrated concrete due to the considerable reduction of voids and the water absorption rate. It is recommended that cement users be mindful of the grade of cement they use to achieve a targeted strength. Structures like water retaining structures, bridges, slabs, beams, columns, etc., which require high compressive strength, should be adequately vibrated.