Comparative Study on the Effects of Steel Slag Aggregate over Blended Cement Concrete

Concrete is the most versatile construction material because it can be designed to withstand the harshest environments while taking on the most inspirational forms. Engineers are continually pushing the limits to improve its performance with the help of innovative chemical admixtures and alternative construction materials (ACM). Nowadays, most concrete mixture contains alternative construction materials which form part of the cementitious component. These materials are majority byproducts from other processes. The main benefits of ACM (alternative construction materials) are their ability to replace certain amount of cement or aggregates and still able to display major properties similar to concrete, thus reducing the cost of using traditional materials. The fast growth in industrialization has resulted in tons and tons of byproduct or waste materials, which can be used as ACMs (alternative construction materials) such as marble powder, silica fume, ground granulated blast furnace slag, steel slag etc. The use of these byproducts not only helps to utilize these waste materials but also enhances the properties of concrete in fresh and hydrated states. Most concrete produced today includes one or more ACM (alternative construction materials). For this reason, their properties are frequently compared to each other by mix designers seeking to optimize concrete mixtures. To design high strength concrete good quality aggregates is also required. Steel slag is an industrial byproduct obtained from the steel manufacturing industry. This can be used as aggregate in concrete. It has been usually used as aggregate in hot mix asphalt surface applications, but in the present work it has been used in conventional concrete mixture and performance is compared with normal aggregate concrete. Replacing all or some portion of natural aggregates with steel slag would lead to considerable environmental benefits. Steel slag aggregate generally exhibit a propensity to expand hence steel slag aggregates are generally not used in concrete making. However, use of blended cement concrete is reported to reduce the expansion of the concrete. In the present work a series of tests were carried out to make comparative studies of various mechanical properties of concrete mixes prepared by using normal cement concrete, marble powder and cement blend concrete (1:1 proportion) with or without use of steel slag. The ingredients are mixed in 1: 1.5: 3 proportions. The properties studied are 7 days, 14 days and 28 days compressive strengths, workability and surface hardness.