COMPARATIVE ANALYSIS OF THE PROPERTIES OF CONCRETE PRODUCED WITH PORTLAND LIMESTONE CEMENT (PLC) GRADE 32.5N AND 42.5R FOR USE IN RIGID PAVEMENT WORK

Abstract

The properties of different grades of concrete produced with Portland limestone Cement (PLC) grades 32.5N and 42.5R was compared in the study. Initial and Final setting time tests were perform on cement paste. Slump and compacting factor test were performed on fresh concrete. Mix ratios of  1:2:4  and  1:3:6 (Cement: Sand: Granite) by volume and mix proportions for Grades 30 and 40 concrete used in different aspect of rigid pavements, were used to cast  concrete cubes  and beams that were subjected to compression and flexural strength test after curing for 7, 14, 28 and 56 days respectively. Compressive and flexural strength values of concrete produced with PLC grade 42.5R were higher than values obtained with grade 32.5. The 28 day compressive strength values of concrete produced with PLC grade 42.5R  were, 28.0, 30.0, 35.0, and 40.0 N/mm, 2 while values of 22.0, 28.0, 33.0 and 35.0 were obtained with PLC grade 32.5, for mix ratios of 1:3:6, 1:2:4 and Grade 30 and 40 concrete respectively. Similar trend was observed with flexural strength values.  Based on result of test PLC grade 42.5R is an improvement over grade 32.5 and its usage in rigid pavement construction work is recommended as it ensures higher strength and economy in concrete work.