Laboratory evaluation of permanent deformations of steel slag asphaltmixture modified Bitumen

Due to the complex behavior of asphalt pavement materials under various loading, pavement structure, andenvironmental conditions, accurately predicting the permanent deformation of asphalt pavement is challenging.To predict the permanent deformation, it is required to find the mathematical relation between the input andoutput data by an accurate and simple method. A total of ۲۷۰ asphalt mixtures were constructed from twodifferent aggregate sources (natural and steel slag) and modified by micro silica and Nano Tio۲/Sio۲. Allsamples were tested at three different testing temperatures of ۴۰, ۵۰, and ۶۰°C and five stresses of ۱۰۰ to ۵۰۰Kpa. Results show that an increase in the percentage of Nano-additives is very effective at reducing the finalstrain of asphalt mixtures. However, an increase in the percentage of additives over ۸.۵% does not help toreduce permanent deformation under dynamic loading in the asphalt mixtures.