DETERMINATION OF UNSATURATED SOIL PROPERTIES FROM SIMPLIFIED EXPERIMENTAL PROCEDURES

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2023-1-27
Kenanoğlu, Melih Birhan
Unsaturated soil mechanics provides theoretical basis to researchers and practitioners for the solution of various geotechnical engineering problems. The implementation of developed theories and experimental techniques into engineering practice is, however, questionable. The development of simple and rapid experimental procedures that are compatible with existing theoretical models could be beneficial in this regard. In this study, a complete framework of practical procedures for obtaining unsaturated soil properties was presented. An experimental campaign consisting of saturated isotropic and K0 consolidated drained triaxial tests and constant suction and constant water content unsaturated tests on a variety of soil types is accomplished in this study. Novel test setups were developed for soil water retention curve extraction and testing of unsaturated specimens. The experimental data is used to validate the effectiveness of developed practical procedures. The first recommended procedure concerns practical and rapid methods for adjusting the water content of test specimens. Another study presents a simple approach for the estimation of shear strength of unsaturated soils for which an experimental parameter that can be easily calibrated with the vi evaporation test is employed. The hydraulic conductivity function of unsaturated soils is estimated from a straightforward numerical algorithm developed for the solution of the 1-D seepage problem during soil water retention curve measurement with axis translation technique. Finally, simple and rapid UU and oedometer tests are performed on unsaturated soil samples. The results from these tests, together with soil water retention curve measurements, are processed to determine the Barcelona Basic Model parameters.

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Citation Formats
M. B. Kenanoğlu, “DETERMINATION OF UNSATURATED SOIL PROPERTIES FROM SIMPLIFIED EXPERIMENTAL PROCEDURES,” Ph.D. - Doctoral Program, Middle East Technical University, 2023.