Faculty Publications
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Item A Comparative Study on Using Laterite and Sandstone Aggregates on Mechanical Properties of Concrete(Springer Science and Business Media Deutschland GmbH info@springer-sbm.com, 2021) Gayana, B.C.; Ram Chandar, K.R.; Reddy, K.R.Scarcity of natural aggregates in concrete construction is leading to explore the use of alternative materials, especially various industrial waste products. Mining industry is one such major source of waste materials. Sandstone, which is overlying coal seams, is the largest quantity of waste rock being produced by coal mining industry. Laterite is another waste comes from small scale quarries. An attempt is made to assess the use of laterite-GGBS and sandstone as partial replacement for sand in concrete. Sandstone samples were collected from the dumps of a coal mine in south India and laterite samples were collected from different quarries from the southwestern part of India. Various properties of mine waste samples were determined in the laboratory as per IS codes, the properties were found to be very close to that of natural river sand. Mix proportions were prepared for M20 grade concrete. Mechanical properties of concrete with different mixes (0, 25, 50, 75, and 100% replacement with sand) were determined and compared. As a result, the concrete mixes with the replacement of fine aggregates with 100% sandstone increased in strength properties i.e., compressive, splitting tensile, and flexural strength compared to laterite mixes, where the strength properties decreased with increase in replacement levels. This indicates that sandstone can be an effective replacement for the river sand in concrete. © 2021, Springer Nature Switzerland AG.Item Development of energy efficient organic bricks in construction using IOT and perlite(Taylor and Francis Ltd., 2021) Shubhananda Rao, P.; Ram Chandar, K.R.The study focuses on improvement of bricks in mechanical properties, reduction of energy consumption, making more economical and environmentally friendly by saving the depleting resources. The bricks were mixed in different proportions, by replacing sand with Iron Ore Tailings from 30 to 60 percent at 10 percent interval, cement from 10 to 20 percent at 5 percent interval and perlite at 2 and 5 percent to make bricks of 230 mm×112.5 mm×75 mm dimensions. The bricks were tested for compressive strength, water absorption and thermal conductivity. From these tests among different combinations, IOTs:Sand:Cement:Perlite 50:25:20:5 combinations have yielded better results by satisfying Indian Standard (IS) codes and this is taken as optimum dosage of raw materials. Model rooms are constructed using these bricks to access the effectiveness of thermal conductivity to compare with the ordinary conventional brick (fired brick) room, both rooms are of the same dimension and exposed to same environmental conditions. Thermal conductivity is assessed by measuring the temperature on walls of all sides of the room at different timings of the day. The results revealed that heat transferred from the outside to inside of the walls of the model room constructed with IOT-perlite bricks was at least 2°C less compared with that of ordinary bricks. Lower thermal conductivity leads to energy savings and results established 8 percent of energy savings with IOT-perlite bricks. The study proved the eco-friendly bricks by using the mine waste, lower thermal conductivity, good strength and light weight in structure. © 2020 Informa UK Limited, trading as Taylor & Francis Group.