Abstract

Concrete is the most demanding construction material capable to consume high volumes of industrial waste such as fly ash, which is regularly generated in large quantities as a by-product in thermal power plants. A considerable quantity of fly ash remains unused and mismanaged disposal poses threat on different dimensions of environment. The development of sintered lightweight aggregate combined with fly ash is a suitable method to combat with the fly ash waste management issues. The preparation and application of pervious lightweight aggregate in concrete structure gained less attention due to absence of feasible mix design method. The durability and absorption properties of lightweight aggregate must be considered while preparing mix proportions of pervious concrete. The present study is an attempt to give a brief analysis of durability and water absorption properties of fly ash based pervious concrete (FPC) which was prepared by sintered fly ash aggregate, a more reliable and simpler than the existing methods. The experiments were carried out by exposing the fly ash based pervious concrete material towards various chemical attacks such as sodium sulphate, sulphuric acid, and seawater under different curing period. To validate the characteristics of proposed fly ash based pervious concrete material, twenty-one trail mixes were prepared employing varied water to cement and cement to aggregate proportions. The 4.75, 9.5 and 12mm aggregate sizes, an admixture and 5-15% weight of cement were used in this investigation. Test results indicated that the strength and weight loss in concrete specimens due to sodium sulphate, acid, and seawater attack increases with an increase in cement to aggregate ratio and water to cement ratio. The observations revealed that mix proportion comprising 1:3 cement to aggregate ratio exhibited better durability performance with low water absorption value over others.

Keywords: Fly ash; Waste management; Pervious concrete; Durability; Water absorption Properties; Construction material