Performance characterization and life cycle assessment of semi-flexible pavement after composite modification of cement-based grouting materials by desulfurization ash, fly ash, and rubber powder

This study aims to carry out the performance characterization and life cycle assessment (LCA) of SFP after composite modification of cement-based grouting materials by desulfurization ash (FGD ash), fly ash, and rubber powder. The results of performance evaluation and scheme optimization of various cement-based grouting materials show that after the synergistic use of desulfurized ash and fly ash, the performance of the mixed cement-based materials is close to that of ordinary portland cement. On this basis, after adding 5 % by weight of rubber powder treated with a 2 % concentration of silane coupling agent (SCA) solution, the strength, toughness, and volume stability of cement-based grouting materials are significantly improved, and the comprehensive performance index can be increased by 70 % or more, and the durability of SFP can be increased by 30 % or more at the maximum. SFP's energy consumption and emissions are mainly affected by the raw material production stage, in which cement accounts for 90 % or more of the energy consumption and emissions in the raw material production stage. After the reasonable replacement of cement and keeping good durability of SFP, the energy consumption of SFP in the whole life cycle can be reduced by about 30 %, and the environmental impact can be reduced by 30 % similar to 40 %.