Evaluation of environmental performance and life cycle costs of construction materials: The case of alternative mastic asphalt mixes

Abstract

A procedure for environmental and economic evaluation of construction materials is presented. The selection of appropriate construction materials depends on their technical suitability in particular engineered infrastructures, but also on environmental and economic considerations. The latter can be evaluated in a freely available software, combining principles of Material Flow Analysis (MFA), Life Cycle Energy Analysis (LCEA) and Life Cycle Costing (LCC). With the proposed procedure, different construction options can be compared and an optimal option can be selected. The evaluation procedure is illustrated in a case of mastic asphalt (MA) road surface layers. The production temperature of MA can be reduced my material modifications (application of additives and varying aggregate geometries). Temperature reduction induces changes in material demand, energy demand and costs on various stages of the life cycle. A reference MA is compared to two modified, temperature-reduced mixes with similar mechanical characteristics. The results indicate that the application of a binder additive is controversial and that the complete or partial substitution of crushed aggregates by round aggregates is promising. In either case, reduction of mixing temperature results in reduction of particulate emissions and decreased energy demand. The presented evaluation procedure helps to identify cost-effective, energy-saving and low-emission MA options.