Effect of the Interfacial Zone on the Tensile-Damage Behavior of an Asphalt Mixture Containing MSWI Bottom Ash Aggregates

Abstract

Output of municipal solid waste incineration (MSWI) can be classified as several different types of residues, of which bottom ash is a primary by-product. Utilization possibilities other than landfilling the incineration residues have been a tough task; most initiatives in this sense tend to use these residues as aggregate substitute materials in asphalt pavement. From previous research work, the use of MSWI bottom ash aggregates in asphalt pavement is feasible from the point of view of both environmental safety and structural stability. However, the MSWI bottom ash aggregates are highly multicomponent materials that consist of glass, brick, ceramics, metal, and slag. The compositional variability of bottom ash may affect the damage behavior of asphalt mixture considering that the strength and thickness of the interfacial zone are quite different for each aggregate-asphalt pair. Therefore, based on the finite-element method, numerical simulation has been conducted to investigate the effect of interfacial zone on the tensile damage behavior of asphalt mixture contained bottom ash under indirect tensile force. The stress distribution characteristics have been studied, and the effect of interfacial zone on the asphalt mixtures’ damage behavior has been discussed. The conclusions can provide a theoretical guide for the forecast and control of the tensile damage caused by the variability of components.