The Uniaxial Tensile Strength of Compacted Expansive Soils

Desiccation cracks are the most prevalent cause of engineering geological problems with expansive soils, and tensile strength is the major restricting component for crack formation and development. To promote the development of the connection between tensile strength and other mechanical indexes, a test procedure was established that can measure uniaxial tensile strength and unconfined compressive strength in the same conditions. Uniaxial tensile and compressive tests were performed on compacted expansive soils with water contents that varied from 12% to 24% and dry densities ranging from 1.4 g/cm3 to 1.6 g/cm3. The suction and pore surface fractal dimensions of the specimens were also measured. The experimental findings reveal that the uniaxial tensile strength and unconfined compressive strength followed similar trends as degree of saturation increases and are significantly reliant on suction variations. Then, tensile-compressive-strength ratio and pore surface fractal dimension are subsequently employed to develop tensile strength prediction models. The models presented above have specific physical implications that compensate for the limitations of the fitted models. Finally, the applicability and limits of suggested models for future applications are examined.