Role of Suction in Unsaturated Soils
DOI:
https://doi.org/10.64862/Keywords:
Unsaturated soil, Matric suction, SWCC, Suction strengthAbstract
Soil suction, which regulates the interaction between the soil's water and air phases, plays a major role in the behavior of unsaturated soils. The shear strength, compressibility, and permeability are greatly influenced by suction, which is made up of matric and osmotic components. The stability and deformation of infrastructures can be impacted by significant changes in soil performance brought on by variations in suction caused by external factors like rainfall or evaporation. For proper prediction and modeling of unsaturated soil behavior, it is consequently crucial to comprehend the function of suction. The ability to include suction as a key variable in geotechnical analysis and design has been significantly improved by developments in constitutive modeling and suction measuring techniques. Many scholars proposed empirical methods to predict the suction strength (matric suction contribution) of unsaturated soils. While some of these methods are based on mathematical fitting techniques; others are based on the soil-water characteristic curve (SWCC) and the saturated shear strength parameters. An improved suction strength formula is put forward in this work. The validity of the proposed improvement method is examined for a few suction strength data of different kinds of soils. It was found that the suction strength values predicted from the proposed equation are in well agreement with the experimental results.
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