Project BUGGY, preshot geologic and engineering properties investigations
Lutton, R. J.; Hunt, Richard W.; Rowland, R. E.
Miscellaneous PaperAbstract: · The site for the Buggy row charge cratering event is located on Chukar Mesa, NTS, in dry basalt. Topography is relatively flat over an approximately square area about 3,000 feet across. The site consists of about 330 feet of horizontal basalt flows resting on tuff breccia, other basalt flows, and a thick vitrophyric flow. Unconfined compressive strengths tend to decrease with increasing porosity from 33,000 psi for dense basalt to 6,200 psi for vesicular basalt with 20 to 30 percent vesicles. Tensile splitting and unconfined and triaxial compression tests on dense basalt indicate a failure envelope with Ø of 50 degrees at normal stresses of 0 to 5,000 psi and Ø of 30 degrees at normal stresses of 15,000 to 20,000 psi. Cohesion is about 5,000 psi. The Poisson's ratio for basalt ranges from 0.17 to 0.30 and is apparently not related to vesicularity. The weighted lineal joint intercept spacing for near-surface basalt averages about 0.3 foot and that at depth averages about 0.9 foot. Interlayered clinker zones apparently reduce the average seismic velocity of the medium by more than 50 percent. NOTE: This file is large. Allow your browser several minutes to download the file.
U.S. Army Engineer Waterways Experiment Station.Engineer Research and Development Center (U.S.)
Project Buggy; Preshot analysis; Geology; Geologic features; Nevada Test Site; Cratering; Basalt; Excavation; Nuclear weapons; Nuclear blasts
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