Road specialists in the world often suffer the huge challenge in designing a stable road on very soft saline soils, these soils in arid zones have a low bearing capacity with high compressibility and very sensitive to moisture and synchronized with complete collapse. The case study concerned by the deterioration of main road linking between Alsamawa town and Sawa lake approximately 20 km away from Alsamawa town. There are sections of roads affected by converges of nearby local artificial lakes , water drawn from several good drain down to (80) meters depths and causing the deterioration in the road sections , swell-collapse test results represented by a little swell potential values were appeared for zero applied stress, while aggressive collapse were happened with increasing in applied stress, and the increasing in degree of collapsibility corresponding to increasing of applied stress of (50,100,200) KPa, and sodium chloride (NaCl%) in soil layers range between (0.613-16.468) % and slightly to moderately gypseous soils, the case study included several recommendations to treating the deteriorated significantly of road to protect the sub-grade and subbase layer .
Assessing the degradation of vegetation of arid zones using FAO–UNIP model (case study: Kashan zone)