THE EFFECT OF MINING WASTE ON THE DURABILITY INDICATORS OF CEMENT-BASED COMPOSITES

Abstract

The need for infrastructure development is of major importance and the projected global infrastructure investment between 2013-2030 is estimated in the excess of £30 trillion to support the rapid growth of societies and economies worldwide (1). This trend puts civil infrastructure industry under immense stress to plan properly, construct fast and deliver resilient structures. Concrete is the dominant construction material and the key element in most infrastructure assets. However, concrete’s manufacture is extremely energy and resource intensive: >4 Billion tonnes of cement are produced annually, accounting to ~8% of global anthropogenic CO2 and resulting to an annual production of ~2 tonnes of concrete for every person on the planet. The production of concrete is a process associated with very high energy consumption. In Europe, the construction sector alone is responsible for the 36% of CO2 emissions and the 40% of all energy consumption. The utilisation of mining waste in cement-based composites is an area of growing interest worldwide, with mining and excavation waste increasing considerably the last decade. Our work focuses on the replacement of cement with mineral wastes and the initial findings suggest that even at 20% replacement, the mechanical properties are marginally affected. This contribution will discuss some preliminary data on the effect of mining waste on the durability indicators of cementitious composites (oxygen permeability, capillary sorption and ion diffusion). Keywords: Mining waste, Silicates, capillary water absorption,