Sustainable Concrete with Zero Carbon Footprint

This paper describes a method to use solely recycled and by-product materials as constituents to form concrete that can be used in buildings structural applications. As concrete is one of the most important materials in human civilization, where it is used widely in construction, cement and aggregate the main components of concrete cause an emission of large amounts of carbon dioxide, which is the main cause of global warming. The production of one tonne of cement, for example, causes the emission of about 800 kg of this CO<sub>2</sub>. The growing demand for concrete constitutes a threat to the environment and its resources into the future. According to a market study by The Freedonia Group, in 2019 the world demand for cement was 5.1 billion tonnes which means that more than 2.5 billion tonnes of water and more than 11 billion tonnes of aggregates, both of which are scarce resources, will also be consumed. The goal of this Paper is to describe a 100% substitution of concretes normal constituents to form a sustainable concrete with zero carbon footprint and without compromising concrete mechanical properties. This will demand a pre-treatment of the recycled and by-products components to compensate for the natural strength loss due to their inclusion. Therefore, an innovative novel treatment method is selected for recycled concrete aggregates and chipped rubber to be separately treated and tested to mitigate the loss of strength in proposing a novel recycled activator for GGBS and silica fume. Then these waste recyclable materials are combined in a concrete mix that is 100% recycled and, therefore, significantly more sustainable.