• Water content: The lower the soil moisture, the greater the soil suction, the soil suction will maintain its maximum value when the soil is free of any moisture (dry). • Soil plasticity index: Soil suction will be greater in a soil that has a higher plasticity index than in one that has a lower plasticity index. • Drying and wetting history: soil suction is less during the wetting time than during the drying time. • Soil structure: the size of the interstices in a soil depends on the structure of the soil, a change in the formation would lead to a change in the size of the interstices and therefore a change in the suction of the soil. • Temperature: changes in temperature can alter soil suction, an increase in temperature would decrease soil tension and result in a decrease in suction, and similarly, a decrease in temperature would result in an increase in