Influence of Aeration and Curing on Shear Strength of Asphalt Stabilized Soil

Abstract

Asphalt stabilization technique is usually used to control and improve poor subgrade soil condition. The subgrade soil is the foundation for the roadway structure, its responsibility       is to provide the required stability for the overlaying pavement and to limit the deformation due to traffic load repetitions by furnishing homogeneous stress distribution. In this work, the unconsolidated undrained Triaxial test was implemented for comparatively assessing the impact of asphalt stabilization on shear strength and stiffness of asphalt stabilized subgrade soil. Soil samples have been treated with cutback asphalt using various water and liquid asphalt percentages. The loose asphalt stabilized soil samples were subjected to aeration periods ranging from one to five hours at room temperature. Cylindrical Specimens with height and diameter of (77.4 and 38) mm respectively have been prepared in the laboratory after aeration periods using static compaction to achieve a target density. Specimens have been subjected to curing at room temperature for a curing period ranging from seven to ninety days, then tested in the Triaxial apparatus to determine its shear properties. Data have been analyzed and compared. It was concluded that the optimum aeration period was two hours while the reasonable curing period is seven days.