石墨尾矿掺量对沥青胶浆性能的影响OA

Aiming at the dual needs of resource utilization of graphite tailings and sustainable replacement of road engineering fillers,the influence mechanism and optimal dosage of graphite tailings partially replacing limestone powder on the performance of asphalt mortar were studied.The microstructure of graphite tailings and limestone powder was analyzed by scanning electron microscopy(SEM).The asphalt mastic with different content of graphite tailings was prepared,and the high temperature rheology,low temperature rheology and fatigue resistance test were carried out.The results show that when the substitution rate of graphite tailings is 25%,the high temperature performance of asphalt mortar is improved.Compared with limestone asphalt mastic,the Brinell viscosity of graphite tailings asphalt mortar at 135℃increased by 83.3%,the dynamic shear rheological rut factor at 46℃increased by 63.2%,and the peak stress measured by linear amplitude scanning test increased by 32.6%.SEM microscopic analysis shows that the edges of graphite tailings are mostly irregularly serrated and the surface is rough,which can enhance the strength of asphalt-filler interface.The addition of graphite tailings leads to the attenuation of the low temperature performance of asphalt mortar.At-18℃,the creep stiffness increases by 17.7%and the creep rate decreases by 22%compared with limestone asphalt mortar.The research conclusions provide a basis for the high-value utilization of graphite tailings and the development of sustainable road materials.