Development of computer-controlled triaxial test setup and study on multistage triaxial test on sand

Alyousif, Mostafa
Triaxial test is one of the most important tests in geotechnical engineering. Yet, it is not commonly conducted due to its complexity and lack of automated devices in the Turkish market and the high price for those manufactured by European and American companies. This study focuses on developing a fully automated computer-controlled triaxial test for the first time in Turkey and the Middle East. The automation of the new setup is not limited to performing the standard tests, but also includes the advanced and custom tests like Ko consolidation and custom stress paths. Reference conventional triaxial tests are conducted on a well-branded automated device and their results are in agreement with the ones obtained using the developed setup. The second purpose of this study is to investigate the applicability of multistage triaxial test on sand. Various methods are tested to determine which one yields more accurate results that are closer to those found using the conventional triaxial test with three specimens. Fully removing the deviator stress, as opposed to maintaining it, at the end of every stage of shearing is found to give correct results. Stopping stages at peak deviator stresses is found to estimate a friction angle accurately, as opposed to the lower friction angle obtained by stopping at yielding of the specimen.


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Citation Formats
M. Alyousif, “Development of computer-controlled triaxial test setup and study on multistage triaxial test on sand,” M.S. - Master of Science, Middle East Technical University, 2015.