Engineering properties of new-age (Nano) modified emulsion (nme) stabilised naturally available granular road pavement materials explained using basic chemistry

Abstract

Featured Application: The engineering properties obtainable during the construction of road pavement layers using reactive stabilising agents are traditionally determined using a trail-and-error approach based on material indicator tests, some developed more than a century ago. These tests inhibit the limitations associated with an empirically derived test or method, often leading to costly failures. The introduction of proven and applicable nanotechnologies to treat or stabilise granular material for use in pavement layers could result in the rejection of these technologies if not based on the understanding of the basic chemistry of both the stabilising agent and the mineralogy of the granular materials. This article gives a basic explanation of elementary chemistry that will affect the physical engineering properties (stresses and strains) that can be expected using available, proven and cost-effective nanotechnologies to improve granular materials for use in a pavement structure. Abstract: Nanoscale organofunctional silanes have been developed, tested and successfully applied to protect stone buildings in Europe against climatic effects since the 1860s. The same nanotechnologies can also be used in pavement engineering to create strong chemical bonds between a stabilising agent and granular material. The attachment of the organofunctional silane to a material also changes the surface of the material to become hydrophobic, thereby considerably reducing future chemical weathering. These properties allow naturally available materials to be used in any pavement layer at a low risk. In the built environment, scientists soon determined that the successful use of an organo-silane depends on the type and condition of the stone to be treated. The same principles apply to the implementation of applicable nanotechnologies in pavement engineering. Understanding the basic chemistry, determining the properties of the stabilising agent and the organofunctional modifying agent and the chemical interaction with the primary and secondary minerals of the material are essential for the successful application of these technologies in pavement engineering. This paper explains some basic chemistry, which fundamentally influences engineering outputs that can be achieved using New-age (Nano) Modified Emulsions (NME) stabilising agents with naturally available granular materials in all road pavement layers below the surfacing.