EXPERIMENTAL STUDY ON “M25 GRADE RECYCLED AGGREGATE CONCRETE WITH ADDITION OF NANO-SILICA”

Due to growing environmental awareness, as well as stricter regulations on managing construction waste, the world is increasingly turning to researching properties of construction waste and finding solutions on using its valuable component parts so that those might be used as secondary raw material in other constructional branches. Although demolished material is still today considered waste and is categorized in construction waste catalogues, in most countries in the world, it is most definitely not waste, neither by its physical and chemical properties nor according to data on its use as valuable material for different purposes. Considering the specificity of physical and chemical properties of construction materials and a series of possibilities for their use in the field of civil constructions, this report demonstrates the possibilities of using recycled or reclaimed aggregate as partial replacement of natural coarse aggregate in concrete, where recycled aggregate is obtained from demolition of RCC building. To date, these types of wastes have been widely used as aggregate for civil works worldwide. The application of nanotechnology in concrete has added a new dimension to the efforts to improve its properties. Nano materials, by virtue of their very small particle size can affect the concrete properties by altering the microstructure. This study concerns with the use of Nano silica to improve the compressive strength of concrete. An experimental investigation has been carried out by replacing the cement with Nano silica of 2%. The report presents an investigation of mechanical and durability properties of concrete by adding recycled aggregate and Nano-silica as replacement of coarse aggregate in various percentages. The coarse aggregate has been replaced by recycled aggregate accordingly with 30% is by weight of coarse aggregate for M25 mix and the same adding 2% Nano-silica by weight of water and coarse aggregate. The tests have been made to study the strength properties for 7, 28 and 56 days.