Quantitative evaluations on influences of aggregate surface texture on interfacial adhesion using 3D printing aggregate

Abstract

In this work, icosahedral 3D printing aggregate (3DPA) was designed, prepared with three polyamide materials and compared with four natural aggregates for surface texture and difference in adhesion to asphalt. Firstly, the morphological and structural characteristics of 3DPAs were analyzed. Then, four kinds of natural aggregates were compared with 3DPAs for the boiling test to quantitatively evaluate the adhesion of 3DPAs and asphalt. Subsequently, the microscopic images of different aggregates were identified by digital image technology. Finally, the adhesion performance of different aggregates to asphalt was predicted by quantifying the number of edge points. The results show that the adhesion of 3DPAs to asphalt under boiling test is similar to basalt, better than diabase and granite, but worse than limestone. In particular, since 3DPAs are regular icosahedrons, the score can be quantified in the boiling test, which is significantly better than irregular natural aggregates. Digital image processing can accurately identify the microscopic morphology of aggregates and calculate their surface structural characteristics, and the results are basically consistent with the boiling test. 3DPA with regular shape is a method to avoid cutting natural aggregate and quantitatively evaluate asphalt adhesion properties accurately. The research results are helpful to promote the application of 3D printing technology in asphalt pavement.