Analysis of the recyclability of thermosetting pavement materials: A case study of reclaimed epoxy asphalt pavement (REAP)

The sustainable recycling of thermosetting pavement materials is a critical challenge in modern infrastructure. This study addresses this issue by investigating the potential for recycling reclaimed epoxy asphalt pavement (REAP) derived from engineering. Through a series of comparative crushing and abrasion tests, the compressive strength and wear resistance of REAP were evaluated against limestone and basalt as control groups. Surface energy and water immersion tests were conducted to analyze the adhesion behavior of REAP with matrix asphalt and asphalt mastic at three different powder-to-asphalt ratios. Additionally, mixture tests assessed the performance trends associated with incorporating REAP. The findings reveal that REAP exhibits compressive strength between that of limestone and basalt, while its wear resistance is slightly inferior to limestone. Notably, REAP exhibits no significant adhesion deficiencies with the matrix asphalt, achieving the highest adhesion work of 72.48 mJ/m² with asphalt mastic at a filler-to-asphalt ratio of 1.0. However, the water immersion tests indicate that the adhesion between REAP and asphalt mastic is significantly better than that with matrix asphalt, suggesting that the REAP possesses rich textural characteristics. These results highlight the unique surface textural characteristics of REAP produced through mechanical crushing. A mass conversion method was proposed for designing mixture gradation, effectively minimizing fluctuations caused by density differences between REAP and natural aggregate. Mixture performance tests show that the incorporation of REAP has a significant impact on crack resistance and water damage performance, particularly when combined with natural aggregates. • The recyclability of thermosetting pavement materials was explored. • No significant defects in the adhesion was observed between REAP and the asphalt binder. • A mass conversion method was proposed to control the gradation. • The structural strength of REAP particles was analyzed.