Investigating some properties of concrete using different brands and grades of ordinary portland cement in the Ghanaian market

Abstract

This study was on investigating some properties of concrete using different brands and grades of ordinary Portland cements in the Ghanaian market. This study examines some mechanical properties (compressive, flexural and modulus of elasticity) of concrete made from Ghacem, Supacem, Cimaf and Diamond cements. In this work, four different ordinary Portland cement brands and two grades of 32.5R and 42.5R were used. The samples were tested after 28 and 90 days of curing age. Concrete cubes of size 100mm×100mm×100mm and beams size of 500mm x 100mm x100mm specimens of mix 1:1.5:3 with water-cement ratio of 0.55 were prepared and tested. The specimens were cured using water-submerged curing as stipulated in (ASTM C31 / C31M – 21). The workability of the fresh concrete was determined using the slump cone test conforming to ASTM C143 (2005). The compressive, flexural and modulus of elasticity strength tests were conducted in accordance with the American Society for Testing and Materials (ASTM) code of practice ASTM C39 (2003), ASTM C78, 2002 and ASTM C469 respectfully. The study recorded a higher slump value of 58mm and 60mm for 32.5R and 42.5R grades of cement. The average density recorded at the 28 and 90days test was 2293.67 (kg/m3) and 2319.67(kg/m3) respectively. The average compressive strength at 28 and 90days was 26.527 N/mm2 and 29.26 N/mm2 for 32.5 and 42.5 grades of cement. After the flexural test, an average value of 5.04 N/mm2 and 7.12 N/mm2 was achieved at 28 and 90days for 32.5 and 42.5 grade of cement. 10474 N/mm2 and 15899 N/mm2 average values were obtained after the modulus of elasticity tests. The results indicated that all the cement used meet the minimum requirements as stipulated in BS 8110: Part 1 (1997) table 5.4. and BS 8110-2: 1985 (table 7.2) respectively. The study recommends that, grade 32.5R of all cement could be used for structural work, however, for elements of structural importance 42.5 R is recommended.