Improvement of desert areas and their application in road construction(Case study: Khor - Arababad axis of South Khorasan)

In order to study the physical and mechanical properties of available soils in the Khor-Arab Abad road, the seven sampling stations were selected along the way at the distance of 10Km from each other that located on the edge of the road. Then lime is usually the first option for soil stabilization in road construction projects as an economic reason. Considering the existence of Magnesium Oxide production factory in southern Khorasan province, this option has been studied also as a stabilizing agent in the present study.the existence of the Qaleh-Zari copper mine near Khor-Arab Abad road was a motivation to study the application of utilizing copper waste of processing factory for stabilizing soil .In order to specify the optimum amount of lime, the samples containing 2%, 5% and 10% of Lime were prepared. The optimum percentage was selected to be 5% according to previous studies and related recommendations was proposed 2% of lime adding to half of the samples as an accelerator for magnesite and copper waste respectively. Three additive combinations of 5% lime, 5% fine-grained magnesite with 5% lime, 5% copper waste have shown the best performance in order to increase CBR, uniformity of effect on all samples and non-inflation of 7 days treated samples. In terms of uniformity of performance on increasing CBR, the condition of fine- grained magnesite situation is better than copper waste and weaker than lime.