A comparative study on life cycle analysis of cold mix and foamed mix asphalt

Abstract

Abstract Cold mix asphalt (CM) technology is more sustainable and environmentally friendly than hot mix asphalt (HM) technology. The cold mixtures are prepared with aggregates, asphalt emulsion, and water at ambient temperature. The cold mix is used to achieve economic and ecological benefits but is used to a limited extent due to its low strength and high-water sensitivity. Some additives like Ordinary Portland cement, chemical stabilizers, fibers, cement kiln dust, limestone, and fly ash are added to enhance the strength and stability of cold mix asphalt and reduce the susceptibility to moisture. Foamed mix asphalt (FMA) is a unique pavement construction method for enhancing new granular materials. Cold water and air molecules are injected into the Writgen WLB 10S machine’s bitumen expansion chamber to produce foamed bitumen. When hot bitumen mixes with cold water, foam creates, and bitumen bubbles emerge during the instantaneous foaming process, known as foaming. The bitumen collected in a cylindrical bucket during foaming is known as foamed bitumen, and the foamed bitumen is used as a binder during mix design and has a low viscosity. Fundamental indicators of FMA are (i) expansion ratio and (ii) half-life. This paper reflects the life cycle analysis (LCA) of CM to hot mix based on different parameters like energy consumption and carbon emission in the cradle-to-gate stages incorporating the effects of various foaming agent contents. Also, the LCA method estimates greenhouse gas emissions at different stages of production, transport, and pavement laying at the site. The greenhouse gas emission is responsible for global warming.