Performance and mechanism of solid waste coking sulfur paste modified asphalt mixture before and after curing

For the resource utilization of the solid waste coking sulfur paste and the improvement of performance of the asphalt mixture, a method for preparing modified asphalt mixture with coking sulfur paste modifier (CSPM) is herein proposed. Compared with the matrix asphalt mixture, the Marshall stability of the 30% CSPM modified asphalt mixture increased by 38.3%, the dynamic stability increased by nearly one time (reaching 1847.5 times/mm), the splitting strength ratio increased by 39.3% while the splitting tensile strength decreased by 11.7%. After curing, the performance of the CSPM modified asphalt mixture was further improved. The results show that CSPM improved the high temperature stability and water damage resistance of the asphalt mixture, and the low-temperature anti-cracking performance of that was slightly reduced. Chemical analysis of asphalt binders shows that a little sulfur reacted with asphalt to produce polysulfide compounds (R-S-x-R '), and a part of sulfur existed in the form of crystalline sulfur which was further increased after curing. The presence of crystalline sulfur as an inorganic filler is the key point for improving the high temperature stability and water resistance performance of modified asphalt mixture.

Automated summary

The method of preparing modified asphalt mixture with CSPM improves the performance of the asphalt mixture, increasing Marshall stability and dynamic stability while decreasing splitting tensile strength. Chemical analysis shows sulfur reacts with asphalt to improve high temperature stability and water resistance.