2009 Portland GSA Annual Meeting (18-21 October 2009)

Paper No. 58
Presentation Time: 9:00 AM-6:00 PM

IMPROVING APPROXIMATIONS OF THE MOHR-COULOMB FAILURE ENVELOPE


AMUNDSEN, Jesse and JOHNSON, Sarah, Physics and Geology, Northern Kentucky University, SC 204, Nunn Dr, Highland Heights, OH 41099, amundsenj1@nku.edu

In order to more accurately find the Mohr-Coulomb failure envelope, differential calculus is used to find the angle of internal friction and the cohesion of a material. Further methods for solving for the failure envelope are explored using iterative methods in MATLAB. Determining an accurate failure envelope is important to risk assessment, engineering geology and a variety of other disciplines. A comparison of the two primary methods of explicit differential calculus and iterative approximation is discussed. In order to illustrate the explicit method a simple problem containing only two stress samples is completed. The iterative method is revealed to be a more preferable and realistic approach when approximating the failure envelope due to its scalability, speed and acceptable accuracy. Using the automation of the iterative approximation method it is possible to solve for best-fit failure envelopes for a large volume of data which could prove useful when assessing the potential failure of slopes and faults.