Prediction of matric suction of unsaturated soil based on electrical resistivity

Application of unsaturated soil mechanics to practice requires measurement of soil suction, but suction measurement can be expensive, difficult, and often impractical to obtain with the normal used methods. A model for predicting the matric suction of unsaturated soils from soil electrical resistivity measurement is proposed. Based on the laboratory test results, the corresponding electrical resistivity parameters of (F) over bar, (f) over bar and A are calculated; where (F) over bar, (f) over bar and A are average formation factor, average shape factor and anisotropy index respectively. The variation of these three electrical resistivity parameters and matric suction with volume water content are studied, respectively. The parabola relationship between the comprehensive structural parameter R-e and matric suction is identified. A parabola equation of R-e and matric suction is proposed. Prediction of matric suction from electrical resistivity measurement allows for a simple, inexpensive and practical description of the behavior of unsaturated soil.