Development of Nondestructive Evaluation Techniques for Large Rock Specimens.
Foster-BE; Snyder-SD; McClung-RW
NTIS: Ornl/tm-4899 Available for Reference At Bureau Libraries :72 pages
High-voltage radiography was performed on specimens of limestone shale, and sandstone, both unstressed and stressed by one of four selected expansion anchors. Experiments were conducted to optimize the techniques for producing the radiographs and the quantitative microdensitometry on radiographs of stressed and unstressed blocks. A unique microdensitometry scanning and data processing system using correlation techniques was developed so that a subtle difference previously unobservable could be extracted from the background and recorded. Multiple sets of specimens of limestone and sandstone, both unstressed and stressed by each of eight expansion anchors, to examine qualitatively the range of possible anchor-rock specimen combinations of interest to rock-mechanics researchers. Experiments were conducted on simple beam specimens of limestone stressed in both compression and tension to develop an understanding of the radiographic phenomenon, and quantitative relationships between changes in x-ray transmission and stress.
CP; Final Contract Report;
NTIS Accession No.
NTIS: Ornl/tm-4899 Available for Reference At Bureau Libraries
Oak Ridge National Lab.