The purpose of this study was to investigate the PARTIAL REPLACEMENT OF NATURAL SAND BY MICROFINES FOR CEMENT CONCRETE. The suitability of crushed stone dust waste as a fine aggregate for concrete has been assessed by comparing its basic properties with that of conventional concrete. Two basic mixes were chosen for natural sand to achieve M25 and M30 grade concrete. The equivalent mixes were obtained by replacing natural sand by stone dust partially and fully. The test results indicate the crushed stone dust waste can be used effectively to replace natural sand in concrete. In the experimental study of strength characteristics of concrete using crushed stone dust as fine aggregate it is found that there is increase in compressive strength, flexural strength and tensile strength of concrete. 

Natural resources are depleting worldwide while at the same time the generated wastes from the industry are increasing substantially. The sustainable development for construction involves the use of nonconventional and innovative materials, and recycling of waste materials in order to compensate the lack of natural resources and to find alternative ways conserving the environment. So, this paper presents the results of an experimental investigation carried out to evaluate the mechanical properties of concrete mixtures in which fine aggregate sand was replaced with Copper Slag. The fine aggregates sand was replaced with percentages 0 for the control mixture , 10 , 20 , 30 , 40 , 50 , 60 , 80 , and 100 of Copper Slag by weight. Tests were performed for properties of fresh concrete and Hardened Concrete. Compressive strength and Flexural strength were determined at 7, 28 and 56days. The results indicate that workability increases with increase in Copper Slag percentage. Test results indicate significant improvement in the strength properties of plain concrete by the inclusion of up to 80 Copper slag as replacement of fine aggregate sand , and can be effectively used in structural concrete. Also as percentage of Copper Slag increased the density of concrete increased. The workability of concrete increased with increase in percentage of copper slag. Toughness of copper slag is found to be more, which increases the compressive and flexural strength of concrete. 

Natural resources are depleting worldwide while at the same time the generated wastes from the industry are increasing substantially. The sustainable development for construction involves the use of nonconventional and innovative materials, and recycling of waste materials in order to compensate the lack of natural resources and to find alternative ways conserving the environment. So, this paper presents the results of an experimental investigation carried out to evaluate the mechanical properties of concrete mixtures in which fine aggregate sand was replaced with Copper Slag. The fine aggregates sand was replaced with percentages 0 for the control mixture , 10 , 20 , 30 , 40 , 50 , 60 , 80 , and 100 of Copper Slag by weight. Tests were performed for properties of fresh concrete and Hardened Concrete. Compressive strength and Flexural strength were determined at 7, 28 and 56days. The results indicate that workability increases with increase in Copper Slag percentage. Test results indicate significant improvement in the strength properties of plain concrete by the inclusion of up to 80 Copper slag as replacement of fine aggregate sand , and can be effectively used in structural concrete. Also as percentage of Copper Slag increased the density of concrete increased. The workability of concrete increased with increase in percentage of copper slag. Toughness of copper slag is found to be more, which increases the compressive and flexural strength of concrete. 

Concrete is the leading construction material in the region of the world and used in structural works, including infrastructure, low and high rise buildings. It is a man made artifact, essentially consisting of a combination of cement, aggregates, admixture s and water. Inert granular materials such as natural and crushed stone or gravel form the main part of the aggregates. Conventionally aggregates have been available at economical prices as well as of qualities to suit the entire purposes. But, the continued wide withdrawal of aggregates has been questioned as of the depletion of quality main aggregates and greater awareness of environmental safety. In this research, I have replaced the coarse aggregate partially by using asbestos cement sheet waste. Therefore, I have planned to prepared some number of cubes and beams, using asbestos cement sheet waste at various proportions like 0 , 5 , 10 and 15 by weight of coarse aggregate The properties for fresh concrete are tested for Compressive Strength and flexural strength at the age of 7, 14 and 28 days. It is found that with the increase in the percentage replacement of coarse aggregate with Asbestos sheet waste there is increase in Compressive Strength and Flexural Strength upto5 replacement after that there is a decrease in Compressive Strength and Flexural Strength with the further replacement of coarse aggregate with Asbestos sheet waste. It can also observe that 28 days Compressive Strength and Flexural Strength are increased by replacement of coarse aggregate with Asbestos sheet waste as compared to conventional concrete.