APPLICATION AND COMPARISON OF MULTISTAGE TRIAXIAL COMPRESSION TEST PROCEDURES ON RECONSTITUTED ANKARA CLAY

2022-5-11
VAKILINEZHAD, AMIRAHMAD
The ability to conduct conventional triaxial compression tests on multiple identical specimens is restricted by available sample quantity, sample homogeneity, as well as testing duration. Multistage triaxial testing is an alternative method to tackle this issue by using a single specimen, sheared under different confining stresses to attain the strength parameters. Although there are widely accepted procedures to decide when to stop each shearing stage and proceed to the next stress level, the applicability of these procedures on different soil types is still a question. This study examines the applicability of three MST procedures (Rational Procedure, Minimum Slope and Maximum Curvature) under two different deviator stress conditions (Sustained or Cycled) during confining stress increase. The outcome is compared to conventional triaxial test results for both drained and undrained shearing of reconstituted specimens of high-plasticity Ankara Clay. Out of the six options, the rational procedure with cycled deviator and minimum slope with cycled deviator approaches are respectively found to give the most accurate strength parameters in reference to undrained single stage and drained single stage test results. The maximum applicable number of the shearing-reconsolidation sequences before strength loss is also investigated for each MST procedure.

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Citation Formats
A. VAKILINEZHAD, “APPLICATION AND COMPARISON OF MULTISTAGE TRIAXIAL COMPRESSION TEST PROCEDURES ON RECONSTITUTED ANKARA CLAY,” M.S. - Master of Science, Middle East Technical University, 2022.