Accession Number : AD0782874

Title :   Rock Strength from Failure Cases: Left Bank Slope Stability Study Libby Dam and Lake Koocanusa, Montana.

Descriptive Note : Technical rept.,


Personal Author(s) : Hamel,James V.

Report Date : JUN 1974

Pagination or Media Count : 250

Abstract : Slope stability problems involving fault and joint bounded rock masses occurred in the left abutment and left bank areas of Libby Dam during recent construction of the dam and related facilities. These problems were investigated by the Seattle District and Waterways Experiment Station, Corps of Engineers, and by the author. Results of these investigations are summarized in this report where emphasis has been placed on determination and interpretation of in situ shear strengths for geologic discontinuities in hard rock slopes. It was impossible from a practical standpoint to obtain the degree of geologic information needed to reliably evaluate the stability of left bank rock ribs. This is largely because of the size of the ribs and the complexity of their structural geology. Despite this lack of geologic information, several conclusions of practical importance were drawn from the investigation. These conclusions are related to failure conditions for small rock wedges, in situ shear strength parameters for geologic discontinuities, and left bank rib stability. (Modified author abstract)

Descriptors :   *Dams, Slope, Stability, Faults(Geology), Tectonics, Geologic formation, Rock mechanics, Joints, Montana

Subject Categories : Geology, Geochemistry and Mineralogy
      Civil Engineering

Distribution Statement : APPROVED FOR PUBLIC RELEASE