To obtain reliable and consistent shear strength results, which are essential in the design of earth structures, from triaxial tests, careful attention, skill, and judgement must be given to testing procedures and equipment make-up. There are many sources of potential errors in the test, especially when pore pressures are monitored. Consequently, a question inevitably arises concerning tbe quality of triaxial test results obtained by different geotechnical laboratories. The intent of this study was to initiate and help establish a triaxial testing forum whereby any geotechnical laboratory engaged in triaxial testing can check the quality of their triaxial results, and therefore, evaluate their testing procedures and equipment make-up agamst the results obtained by other agencies. To initiate the forum, isotropically consolidated, undrained triaxial tests with pore pressure measurements were performed by three agencies -- the Divisions of Research and Materials of the Kentucky Department of Transportation and the Civil Engineering Department of the University of Kentucky -- on remolded, "standardized" kaolinite specimens. The triaxial results reported by each agency and analyses of all data by the Division of Research are reported and shows that the three participating agencies obtained about the same results. The forum will be useful to any governmental agency for accrediting any geotechnical laboratory performing work for that agency.

Report Date


Report Number

No. 533

Digital Object Identifier



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