Executive Summary : | Cold Mix Asphalt (CMA) is considered as a sustainable alternative to hot mix asphalt. Since the preparation of cold mix does not require any heating, adaptation of cold mix in highway construction helps reduce carbon footprint. In general, it was observed that the performance of conventional CMA does not superior performance and economic value proposition in comparison with the Hot Mix Asphalt (HMA). Thus, CMA is popularly considered as candidate mix for base course, especially in low and medium traffic conditions. Although there exists a scope of sustainability traits of pavement construction using CMA, it poses few challenges both in structural and constructional perspectives. These challenges include but not limited to: higher air voids, moisture damage, longer construction time due to curing. Several research studies explored ways to improve the performance of CMA and highlighted that it is possible to circumvent the difficulties of CMA through modification using various additives such as: fly ash, fibre, lime, polyvinyl acetate, cylinder oil, etc. Though the literature provided an initial understanding of the mix design methodology and material selection of CMA, the lack of inclusive methodology for quantifying performance can easily be ascertained. Thus, it is deemed important to develop and upgrade mix design procedure with which superior performing CMA can be prepared. It is for majorly for two reasons: (a) draw comprehensive understanding of additive and its impact, and (b) design CMA which can stand medium to high traffic conditions. With this background, this research effort aims at developing and evaluating performance of CMA with additive for high traffic condition. Such study will help draft new sets of specifications which will upgrade the state-of-the-art of CMA. The major scope of this study will include but not limited to (i) selection of appropriate additive based on mix composition, (ii) perform mix design to determine optimal set of mix composition, (iii) conduct performance investigation on CMA mix, (iv) finalize volumetric based specification that can offer the best performing CMA mix, (v) perform life-cycle cost analysis and estimate carbon footprint to evaluate the sustainability of CMA mix. A total of seven tasks has been formulated to accomplish the objective of this study over a duration of 36 months. Overall, it is envisaged that research findings will provide a comprehensive methodology and guidelines to develop CMA with additive that can offer superior performance that can be compatible for high traffic condition. |