Study On The Performance Of OGFC Asphalt Mixture Mixed With Recycled Aggregate And Steel Slag Aggregate

In order to solve the problem of open-air stacking of construction waste and steel slag and realize the resource utilization of industrial solid waste,this paper applies the mixture of recycled aggregate and steel slag aggregate to the macroporous open graded noise reduction and drainage(OGFC)pavement,and uses the advantages of high strength and stiffness of steel slag aggregate to improve the road performance of OGFC prepared by recycled aggregate.Therefore,in this paper,the recycled aggregate is replaced by steel slag in the proportion of 0%,25%,50%,75% and100% respectively to prepare OGFC.The optimum stone ratio is determined by Marshall test and leakage test;Then,through the low-temperature crack resistance,high-temperature performance and water stability of the asphalt mixture mixed with two kinds of aggregates,finally,the pore decay and plugging mechanism are studied through plugging test and HD camera imaging.The main research work and conclusions are as follows:(1)The oil stone ratio of OGFC steel slag asphalt mixture increases with the increase of the content of steel slag instead of recycled aggregate,which is 0.5%-1.3% higher than that of natural limestone aggregate OGFC asphalt mixture.(2)The high-temperature performance and water stability of OGFC asphalt mixture prepared from all recycled aggregate meet the requirements of the specification,but the low-temperature performance does not meet the requirements of the specification.(3)The water stability of OGFC steel slag asphalt mixture increases first and then decreases with the increase of steel slag content.When the steel slag content is75%,the water stability performance is the best.(4)The flow value of OGFC asphalt mixture decreases first and then increases with the increase of steel slag content.When the steel slag content is 75%,the flow value is the smallest and the deformation performance is the best.When the steel slag content is less than 25%,the flow value is greater than 4mm,and the deformation performance does not meet the requirements of 2-4mm in the specification.(5)Adding a certain amount of steel slag into recycled aggregate can improve its freeze-thaw splitting strength,but when the proportion of steel slag exceeds 75%,its low-temperature resistance decreases to a certain extent,and the optimal content of steel slag is 75%.(6)Adding steel slag can effectively improve the high-temperature stability of OGFC asphalt mixture.With the increase of content,the high-temperature stability of asphalt mixture increases first and then decreases.When the content of steel slag is50%,the high-temperature stability is the best.(7)The plugging test shows that the water permeability coefficient increases with the increase of steel slag content.When the steel slag content is greater than 75%,the remaining water permeability coefficient after plugging can meet the requirements of the specification ≥ 1200 ml / min.