Response Surface Methodology Optimization in Asphalt Mixtures: A Review

The application of statistical modeling and optimization approaches such as response surface methodology (RSM) is important for the excellent potential to tackle different constraints and goals and the analysis of the relationships between independent factors influencing a particular response. This chapter provides a simple yet detailed literature review on the utilization of RSM for the design of experiments, modeling, and optimization of virgin and alternative materials into asphalt binder and mixtures for sustainability. Meanwhile, an in-depth analysis based on the literature reviewed in terms of asphalt binder modification employing RSM with various independent parameters were summarized. Also, a critical review of the application of RSM to optimize the engineering and mechanical performance characteristics of asphalt concrete mixtures is presented in this chapter. The current chapter concluded that the use of RSM statistical analysis in a highway materials perspective provides a broader understanding of the factors that control pavement performance throughout the pavement service life

Cementitious Grouts Containing Irradiated Waste Polyethylene Terephthalate

This chapter describes a review of the design and formulation of various cementitious grouts for semi-flexible pavement surfaces. Additionally, the authors also conducted extensive experimental work on the possibility of using a most effective and innovative way of recycling waste polyethylene terephthalate (PET) by exposing to gamma radiation and using as a replacement of Ordinary portland cement in the formulation of cement grouts for semi-flexible pavement surfaces. In the current study, cement in the grouts was replaced with PET (regular and irradiated), fly ash and silica fume and was evaluated for flowability and strength properties. The study concludes that normal PET causes a significant reduction in compressive strength, however, some of the strength is restored when irradiated PET was used. The recycling of waste PET, as a cement replacement in the cementitious grouts for semi-flexible pavement surfaces, with the irradiation process can be doubled as compared to utilizing normal/regular PET