Portland State University. Department of Geology
Date of Award
Master of Science (M.S.) in Geology
1 online resource (100 p.)
Geological mapping, Slopes (Soil mechanics), Rock slopes -- Siskiyou National Forest (Or. and Calif.), Geology -- Siskiyou National Forest (Or. and Calif.)
The line mapping method of Piteau and Martin (1977) was tested on two different rock type road cuts in the Siskiyou National Forest, and was found to be an efficient means of collecting geological data for rock slope stability analysis. The unbiased approach of this method calls for close scrutiny of the outcrops in question, covering more ground than other methods in less time. In turn, this close attention to every crack in the outcrop reveals more about the stability of the slope, and can reveal hidden hazards of rock fall.
The supportive systems for analyzing the data - stereonets and computer program packages of Watts (1986) - led to the discoveries of several potential plane and wedge failures which were not initially visible. Also revealed was the fairly stable condition of the massive wedge at Elk River, which appeared to be extremely hazardous.
Each potential failure was analyzed for its Factor of Safety under dry and water saturated conditions, and the cohesion necessary to maintain stability was reported.
Visconty, Greg, "Rock slope stability studies in Siskiyou National Forest" (1988). Dissertations and Theses. Paper 3903.