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The aim of this paper is to investigate the adhesion of municipal solid waste incinerator bottom ash (MSWIBA) and limestone to asphalt using the principles of surface energy theory. MSWIBA asphalt mixes are known for their satisfactory water stability, with adhesion being a crucial factor, as demonstrated in previous freeze-thaw splitting tests. Contact angles of ground MSWIBA and limestone were measured using a capillary rise test, eliminating the influence of material surface structure. Subsequently, adhesion work and spalling work were calculated to correlate with water-induced damage. The results showed that the sequence of adhesion work was fine MSWIBA > limestone > coarse MSWIBA, while the sequence of spalling work was coarse MSWIBA > limestone > fine MSWIBA. The adhesion of MSWIBA asphalt mixes was evaluated using the water boiling test image method to validate the findings of surface energy theory. In both asphalt tests, the spalling rate followed this sequence: coarse MSWIBA > limestone > fine MSWIBA. The Adhesion index ER ranked as follows: ER Fine MSWIBA > ER limestone > ER coarse MSWIBA. These results suggest that the water stability of MSWIBA asphalt mixes is influenced by the surface energy of the components. Consequently, indices derived from surface energy theory can be applied in formulating and predicting the properties of MSWIBA asphalt mixes. [ABSTRACT FROM AUTHOR]

Dispose and utilization of municipal solid waste incinerator bottom ash (MWSIBA) is one of the imperative issues in environmental protection. The applicability of substitution for natural aggregate with MWSIBA in asphalt mixture was investigated by the performance and micro structure of asphalt mixtures with diverse porosity levels of MWSIBA (varying the replacement percentage). The effects of porosity of MWSIBA on asphalt mixture performance were captured by determination of Marshall stability, tensile strength, dynamic stability and the maximum flexural-tensile strain. The horizontal vibration extraction procedure test was implemented for the heavy metal leaching concentration to evaluate the environmental safety of MWSIBA asphalt mixture. Chemical and micro-morphologic characterization for MSWIBA were conducted to explore the mechanism of moisture damage resistance of asphalt mixture. Results indicated that porosity and replacement rate of MWSIBA exerted impacts on properties of asphalt mixture. The rutting resistance of asphalt mixture decreased due to the addition of MWSIBA, resulting in a reduction in high temperature performance. MWSIBA with porosity no less than 19% was beneficial to the improvement of moisture susceptibility and low temperature performance of asphalt mixture, while high mixing amount of MWSIBA was unfavorable to the properties of asphalt mixture. The water immersion stimulated the hydration reaction in MWSIBA, leading to the formation of C-(A)-S-H gel with strong cementation property, which enhanced the adhesion between MWSIBA and asphalt binder. MWSIBA asphalt mixture presented lower heavy metal concentration and better environmental safety than MSWIBA. • The applicability of substitution for natural aggregate with MWSIBA in asphalt mixture was investigated. • Both porosity and replacement rate of MWSIBA exerted impacts on properties of asphalt mixture. • The formation of C-(A)-S-H gel contributed to superior resistance to moisture damage of MWSIBA asphalt mixture. [ABSTRACT FROM AUTHOR]