Mechanical properties of vertical vibration compacted lime-fly ash-stabilized macadam material

This paper studies the mechanical properties of the lime-fly ash-stabilized macadam (LFASM) fabricated via the vertical vibration compaction method (VVCM). First, the reliability of VVCM with respect to the production of LFASMs was evaluated, and their mechanical properties, including unconfined compressive strengths, splitting strengths, and resilient moduli, were studied. Then, the influences of the lime-fly ash (LFA) content, curing time, and gradation type on the mechanical properties of the LFASMs fabricated via the VVCM were discussed. Furthermore, mechanical strength growth equations and relation models were established among the mechanical indexes of the VVCM-fabricated LFASMs. Results reveal that the ratios of the mechanical strength between the laboratory-VVCM-fabricated LFASMs and on-site cores were above 90%. With an increase in LFA contents, the unconfined compressive strength and resilient modulus of the LFASMs increased at first and then gradually decreased, while the splitting strength increased drastically at first and then gently. The aforementioned mechanical properties of the LFASMs increased non-linearly with an increase in the curing times, with potential for improvement via skeleton-dense gradation. The mechanical strength growth properties of the LFASMs can be accurately predicted via the established strength growth equations. Furthermore, the relation models established between the aforementioned mechanical parameters are useful for evaluating the remaining mechanical parameters under the limited test conditions. This study provides a novel alternative for designing and constructing the LFASM base. (C) 2020 Elsevier Ltd. All rights reserved.