Road Damage Due to Expansive Soils: Survey of the Phenomenon and Measures for Improvement

This research work involved surveying major road damages attributed to expansive soils with particular focus on Saudi Arabia. Roads and light structures in various parts of this country experienced damage as a result of moisture increase and environment changes to subgrade soils. Strains in asphalt pavement due to volume change in soils can lead to cracking and attract water seepage to lower formations. An attempt was made to link the road damage to the soil conditions, road geometry and road drainage arrangements. The parameters influencing the swelling process including thickness of pavement, slope of the shoulder, adjacent topography and drainage setup are discussed. Recommendations to achieve better road performance are presented. Applications of cut—off walls and dressing layers are suggested for certain conditions.