From the perspective of sustainable waste management and its environmental impact, waste biomass bottom ash (BA) remains problematic and challenging to use as a recycling material for civil engineering infrastructures. This study evaluated the performance of lateritic soil (LS), stabilized with cement and biomass BA, as a subbase material. BA has been considered a replacement material in LS prior to the introduction of hydraulic cement stabilization means. The geotechnical engineering tests comprised the modified Proctor test, the California Bearing Ratio (CBR) test, and the unconfined compression test. X-ray fluorescence (XRF) and X-ray diffraction (XRD) tests were conducted to investigate the mineralogical properties of the stabilized soil samples. The leachate test was performed with a permeability mold to measure the release of heavy metals. Finally, the benefits of using the stabilized subbase material were assessed using the mechanistic–empirical (M–E) pavement design approach. Based on the results obtained, the strength and stiffness characteristics of the stabilized soils indicate that the efficiency of the mix satisfied the Thailand highway specification. The admixture of 80% BA and 5% cement is suggested for use as a soil–cement subbase material for flexible pavements, due to its good engineering and environmental properties. The results of the M–E design demonstrate the effectiveness of the stabilized soil presented herein. The study’s outcomes are predicted to promote the utilization of waste BA as a promising pavement material.

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This research investigates the effect of corrosion solutions on the mechanical properties of asphalt concrete mixtures. A control asphalt mixture (CM) and five polymer-modified (PM) or filler-modified (FM) mixtures containing waste materials are prepared, namely PM high-density polyethylene plastic (PM-PL), PM crumb rubber (PM-CR), FM Para wood ash (FM-PA), FM palm empty fruit bunch ash (FM-EA), and FM rice husk ash (FM-RA). The experiment is conducted by immersing the mixture specimens in four types of water solutions (i.e., distilled water, alkaline solution, sulfate solution, and acid solution), followed by the splitting tests. Finally, the corrosion resistance factor (fc) is computed to assess the corrosive effect of the corrosion solutions. The results show that the degree of reduction in tensile strength mainly depends on the type of corrosion solutions, type of mixtures, and immersion time. FM-EA provides better resistance under the alkaline and acid solutions, while PM-PL exhibits the greatest fc under the sulfate solution. Among all the mixtures, PM-PL shows the greatest ability in withstanding the corrosion solutions.