GEOL 106 Lecture Notes - Open-Pit Mining, Stress (Mechanics), Factor Analysis

• School: Queen's University
• Department: Geological Sciences and Geological Engineering
• Course: GEOL 106
• Professor: David Alan Hanes

Document Summary

For a particular slope that you are worried about, carry out a safety factor analysis: slope steepness. This determines the probability of failure of that slope (ph) Safety factor: a measure of stability of the slope. The longer t gets, the shorter s gets until angle alpha get to 90 and n will equal zero. Normal stress vs shear stress (review geol 104) S is directly proportional to n; the bigger n is, the bigger s will be. Tan(phi)=a/b (opposite over adjacent)=the slope of the hypoteneuse, or slope of the line. C and than(phi) characterize the strength of the material; it is a straight line! But, replace n with w*cos(alpha): total resisting force=c+(w*cos(alpha)*tan(phi)) A in this equation is the area of contact between the potential failure block and the potential failure plane beneath it. Safety factor greater than 1 means that the slope should be stable, but real answer is maybe/maybe not.