A Comparative Study on M15 and M20 Concrete Strength Variation Using Hand Mixing and Machine Mixing Method

Abstract

Concrete is one of the oldest and most widely used building materials in the world, mostly because it is inexpensive, readily available, has a long lifespan, and can withstand harsh weather conditions. There are many ways to produce concrete in this modern day like Ready mixing, Machine mixing and Hand mixing concrete. The primary goals of this experiment are to determine the most cost-effective concrete and to compare the effects of hand mixing and machine mixing on the compressive and split tensile strengths of concrete.In the current experimental study, concrete mixes with proportions M15 and M20 were used. A total of 72 cylinders, 4 inches in diameter and 8 inches high, were cast and tested experimentally. These cylinders were used to measure the compressive strength and tensile strength of concrete after 7, 14 and 28 days. Samples were removed from the curing tank just prior to testing. A compression test was performed using a compression tester (UTM). We found the maximum compressive strength is 2442 psi for M20 and 2151 psi for M15 concrete by using Machine mix procedure. The value of Hand mix concrete is 1619 psi for M20 and 1431 psi for M15 grade concrete. Again, in the split tensile strength test we get better value for Machine mix rather than Hand mix concrete. So, it is clear that the Machine mixing concrete is more effective than Hand mixing concrete for any types of constructions. Keyword: Hand mixing, Machine mixing, Compressive strength, Split tensile strength, Economical cost.