[CCoE Notice] Dissertation Defense: Comparison and Correction of Multistage Triaxial Tests to Single Stage Triaxial Test for the Rock Mechanical Testing

[Grayson, Audrey A]

COMPARISON AND CORRECTION OF MULTISTAGE TRIAXIAL TESTS TO SINGLE STAGE TRIAXIAL TEST FOR THE ROCK MECHANICAL TESTING

Malik Alsalman
MS Thesis

Defense Date: Friday, April 24th 2015 Time: 3:00pm Location Room: Conference, building 9 ERP
Committee Members: Dr. Michael Myers, Dr. Lori Hathon, Dr. Kasper Willam

The understating of rocks mechanical properties as a function of stress to is required for many geomechanics applications. One is to estimate friction angle and cohesion values to describe the shear strength vs. normal stress over the normal-load range. It is facilitated in the laboratory measurement using Single Stage Triaxial (SST) testing multiple samples at different confining pressures.  Occasionally, due to limited core availability a Multistage Triaxial test (MST) is conducted for the same objective. The uncertainty with obtained results using the two methodologies is not well quantified due the possible changes in elastic properties while loading and unloading the axial stress. Experimental results indicates the consistency of the obtained stress value at the Positive Point of Dilation (PPD) during MST increases the overall results and provides an acceptable correlation between the two methods. Multiple rock types were evaluated representing different lithologies (Shale, Sandstone, and Chalk) to validate a possible single correction factor from MST to SST results that appears to fit the five different rock types. It is  believed that this model fits a wide range of well data from different formations, fields and basins.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://Bug.EGR.UH.EDU/pipermail/engi-dist/attachments/20150421/35260283/attachment-0001.html