Effect of waste glass aggregate on performance of asphalt micro-surfacing

Huge amounts of waste glass are produced every year in China, which brings great pressure on the environment. Meanwhile, a large number of natural aggregates are required for highway construction every year. In this study, it is intended to prepare asphalt micro-surfacing materials using waste glass as aggregate and evaluate their performance. The morphology of basalt and waste glass was quantitatively analyzed through aggregate image measurement system to characterize the morphological differences. In addition, the wet stripping test, wet track abrasion test, wheel load test, sand patch test and British pendulum test were used to investigate the resistance to the action of water, the wear performance, rutting resistance and skid resistance of asphalt micro-surfacing mixtures. The results indicate that the two-dimensional (2D) form of waste glass is more abundant than that of basalt, and as the content of waste glass increases, the British pendulum number (BPN) value and the texture depth (TD) value of micro-surfacing mixtures increase, which means that the addition of waste glass can improve the skid resistance ability of micro-surfacing mixtures to some extent. The abrasion loss, lateral and vertical displacement are all increased after replacing basalt with waste glass due to its brittleness and weak bonding. Considering the feasibility of mechanical properties, it is recommended that the maximum volume amount of fine waste glass and coarse waste glass should be less than 15% and 10%, respectively. The potential use of waste glass can alleviate the overconsumption of natural resources and is a good choice for applying in micro-surfacing pavement materials.