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Warm mix asphalt mixtures became attractive paving mixes by reducing the production temperature to around 25–40 °C as compared to that of conventional hot mix asphalt (HMA). This study aims to evaluate the warm mix asphalt (WMA) using wax-based additives by incorporating two types of industrial wastes. The potential application of low calcium fly ash (FA), i.e. class F type and marble dust (MD), has been evaluated by varying different percentage. The cylindrical samples were prepared and assessed for moisture susceptibility by being subjected to Marshall stability, retained Marshall stability (RMS), indirect tensile strength (ITS) and tensile strength ratio (TSR) tests. Furthermore, the samples were also evaluated for finding the refusal density, Cantabro loss and the rutting performance. A scanning electron microscope (SEM) was also used to evaluate the size and microstructure of the filler particles. The results revealed that the inclusion of fillers into mixes had significant improvement in the mechanical properties and lowered the rutting value with FA and MD addition. The warm mix additive and fillers used were also useful in reducing the binder content of the mixes. The mixing temperature was found to be in the range of 120–130 °C using the warm mix additive. The optimum usage of FA and MD can be up to 5% based on the evaluation. The statistical results reported that there was a significant difference between FA-based and MD-based WMA. [ABSTRACT FROM AUTHOR]

Low-volume roads are anticipated to have less traffic and provide access to socio-economic activities in rural areas. The present study deals with the stabilisation of soil with locally available waste materials, i.e. low calcium fly ash (FA) and brick dust (BD). These two wastes are available abundantly and lead to an increase in pollution levels. Initially, lime was added to make the silty clayey soils plastic-free. The initial consumption of lime was found to be 5%. Then, the soil was stabilised with cement fly ash and cement brick dust techniques for strength, durability and shrinkage evaluation. The cement was varied from 2 to 8% with FA and BD by fixing the ratio to 1:3 as per AASHTO guidelines. The unconfined compressive strength (UCS), indirect tensile strength test and California bearing ratio were conducted for strength evaluation. The wetting and drying cycles were evaluated for durability analysis. The linear shrinkage cracking was evaluated after the curing period of 28 days. It was observed that there was a magnificent increase in strength and durability values. The maximum UCS attained value was so high that it could act as a replacement for the granular sub-base layer in the pavement structure. The linear shrinkage evaluated at fixed relative humidity was significantly reduced. The statistical analysis reported that there was a significant difference between the two admixtures. The utilisation of these wastes not only enhances strength, but also deficits the cost of construction along with reducing the pollutants in the environment. [ABSTRACT FROM AUTHOR]