Separation provides a media between the aggregate and the subsoil which absorbs the load in the form of tension and prevents change in the alignment of the aggregate. Geo-textile economically helps the separation concept of keeping two dissimilar materials apart to maximise the physical attributes of each of those materials. The object of separation by geo-textiles is to prevent a well-defined material or rich material from penetrating the sub-grade or the poor soil. If the separating media of geo-textiles is absent, the infiltration of the sub-grade decreases permeability of the aggregate to the point where it cannot adequately transport the water reaching it. Suitable geo-textile fabric with good puncture/tear resistance when used as a separator media - eliminates the loss of costly aggregate material into the subsoil, prevents upward pumping of subsoil, eliminates contamination and maintains the porosity of different levels. This kind of function finds application in the construction of road and railways tracks, where a geo-textile layer is put beneath the road, to prevent the gravel from mixing into the soil, thus increasing the life of the road by two to three times. For separation purposes, both woven/nonwoven geo-textiles may be used.