Effects of retrieving powder on mechanical and shrinkage properties of vertical vibration compacted cement-stabilized macadam

Abstract

Retrieving powder (RP) is the main by-product of asphalt mixture production, and its application in cement-stabilized macadam (CSM) helps control environmental pollution by reducing the need for waste dumps. To investigate the mechanical and shrinkage properties of CSM that contains RP, CSMs with six RP contents were produced via the vertical-vibration compaction method (VVCM). The unconfined compressive strength (UCS), splitting strength (SPS), drying shrinkage, and temperature shrinkage were evaluated and the mechanical strength prediction model of CSM was established. Then, the factors influencing the mechanical behavior were analyzed. Results show that the compressive strength of VVCM-compacted CSMs had a correlation of 90% with the field-core samples. The mechanical strength growth law of the CSMs can be accurately predicted using the proposed strength prediction model. Moreover, the unconfined compressive strength of CSM demonstrated a parabolic trend with increasing RP content, and an optimum amount of RP existed; however, the splitting strength linearly increased. The drying shrinkage and temperature shrinkage resistance of the CSMs both decreased depending on the increase of RP content but within reasonable limits. This study provides a novel alternative for the design and application of a new pavement structure.