Test Data Overview

One of the major features of RocData is the ability to input strength test data from triaxial or direct shear tests, in order to determine the "best fit" strength envelope and the associated strength parameters (e.g. cohesion and friction angle) for a rock or soil material. The test data can be obtained from lab tests of intact samples, or field data from in-situ rock mass tests.

Obtaining values of strength parameters from actual test data is always recommended, if possible. It should be emphasized that a large number of test results is not always necessary, and good results can be obtained from a relatively small number of data points (e.g. 6 or 7 triaxial tests).

Summary of strength criteria and stress data types analyzed

Triaxial Lab Test Data

Triaxial lab test data can be analyzed with the Use Lab Data option, in conjunction with the Generalized Hoek-Brown, Mohr-Coulomb or Power Curve strength models.

Direct Shear Test Data

Direct shear test data can be analyzed with the Use Lab Data option, in conjunction with the Mohr-Coulomb, Barton-Bandis or Power Curve strength models.

Triaxial Field Test Data

Triaxial field test data can be analyzed with the Use Rock Mass Data option, in conjunction with the Generalized Hoek-Brown strength model.

Curve Fitting Methods

Three curve fitting methods can be used for the analysis of test data in RocData - Levenberg-Marquardt, Simplex, Linear Regression.

Display of Test Data

The test data can be displayed on the failure envelopes in the main RocData view, with the Plot Test Data option.