Experimental Investigation on Strength and Durability Properties of Concrete by Replacing Natural Sand by Manufacture Sand and Fly Ash

Abstract

Durability of concrete is very important factor as it affects the performance of concrete. When the durability aspect of concrete taken into account, the factors affecting it should be given an important consideration as it directly affect the performance of concrete. One such factor is chemical attack on the concrete by sulphate ions (SO-4) which results in the volume change, cracking and consequent deterioration of concrete thus hampering its durability and reducing its strength. The objective of this experimental study is to find out the behaviour of concrete produced by replacing natural sand by Fly ash and Manufactured sand in varying percentages subjected to with sulphate attack and without sulphate attack. Magnesium sulphate solution with concentration of 5% subjected to sulphate attack for 58 days is used in present work. Thus in this research programme the prime attention will be given to find out properties of concrete produced by replacing the natural sand by Fly ash and Manufactured sand in various percentages like 0%, 20%. 40%, 60%, 80%. The mechanical properties such as compressive strength, tensile strength and flexural strength are found and compared for concrete produced by replacing natural sand by Fly ash and Manufactured sand. Keywords: Manufactured sand, fly ash, sulphate attack, compressive strength, split tensile strength, flexural strength. I. INTRODUCTION Ordinary Portland cement is an always demand, expensive and extremely important material in the construction industry. Now in India, it is evaluated that the once-a-year consumption of cement concrete is to the tune of 400metric tones. This will clearly cause an equal demand on the materials like sand, groups and other materials needed to produce huge amount of cement concrete. This will naturally cause reduction of all the valuable things from nature linked in making cement concrete every year. Also the production of huge amounts of cement needs large amount of energy, cause emission of CO2 and carry forward the connected problems. Therefore investigators are concentrating on finding out the additional cementations materials which can replace the cement partially or fully. In this direction, fly ash, blast furnace slag, silica fume, metakaolin and rice husk ash have shown a promising results to replace the cement partially. This way came into existence the blended cements. This way some of the industrial wastes are effectively used in the production of concrete. Fly ash is usually used as replacement of cement, as an admixture in concrete, and in manufacturing of cement. Whereas concrete comprising fly ash as partial replacement of cement poses problems of delayed early strength development, concrete containing fly ash as partial replacement of fine aggregate will have no delayed early strength development, but rather will increase its strength on long-term basis. Fly ash is a by-product of the combustion of pulverized coal in thermal power plants. The dust-collection system eliminates the fly ash, as a fine particulate residue, from the combustion gases before they are discharged into the atmosphere. Manufactured sand is a substitute of river sand for concrete construction. Manufactured sand is produced from hard granite stone by crushing. The crushed sand is of cubical shape with grounded edges, washed and graded to as a construction material. The size of manufactured sand is less than 4.75mm. Manufactured sand is alternative choice for river sand. Due to wild expanding construction industry, the demand for sand has increased very, causing shortage of good river sand in most part of the word. The use of manufactured sand has been increased, due to the reduction of good quality river sand for the use of construction. Another purpose for use of M-Sand is its accessibility and transportation cost. Another important ingredient is river sand. Sand is a naturally occurring granular material composed of finally divided rock and mineral particles. As the term is used by geologists, sand partials range in diameter from 0.0625 to 2 millimeter and individual practical in this range size is termed a sand grain. The next smaller size class in geology is silt: particles smaller than 0.0625 mm down to 0.004 mm in diameter. The next larger size class above sand is gravel, with particles ranging from 2mm up to 64mm. Sand is transported by wind and water and deposits in the form of beaches, dunes, sands spits, and bars and related features.