Study on Theological and chemical behaviors of unaged and aged modified asphalt with solid waste coking sulfur paste

摘要

In this study, solid waste coking sulfur paste was used as raw material to prepare asphalt modifier. Then, the rheological behaviors, storage stability, chemical characteristics and microscopic features of modified asphalt enriched with 10, 20, 30, and 40% of coking sulfur paste granule (CSPG) were investigate. The effects of CSPG on the properties of the modified asphalt after short- and long-term ageing were also studied. The modified asphalt was graded by multiple stress creep and recovery (MSCR) and performance grade (PG) methods. The results show that CSPG decreased the viscosity of modified asphalt and the mixing temperature. The addition of 10% and 20% CSPG improved the anti-cracking ability of modified asphalt at low temperature. Conversely, 30% and 40% CSPG modified asphalt performed better at high temperature with an improved resistance to deformation. The introduction of CSPG strengthened the favorable effect of ageing on the high-temperature properties, but also enhanced the adverse effect of ageing on the low-temperature properties. CSPG modified asphalt also exhibited better storage stability. Furthermore, CSPG can react with asphalt to produce polysulfide compounds (R-S-x-R'), resulting in the increase of large molecular size. CSPG also exists in the form of crystalline sulfur as an inorganic filler to enhance the high temperature anti-rutting ability of modified asphalt. Therefore, 40% CSPG modified asphalt exhibited the best high-temperature performance level, which can withstand very heavy traffic at 70 degrees C (PG70V). (C) 2021 Elsevier Ltd. All rights reserved.