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https://hdl.handle.net/11681/6768| Title: | Project Pre-GONDOLA II : close-in ground motion and earth stress |
| Authors: | U.S. Army Engineer Nuclear Cratering Group. Joachim, Charles E. |
| Keywords: | Nuclear explosion testing Ground motion Shock waves Cratering Nitromethane |
| Publisher: | Weapons Effects Laboratory (U.S.) Engineer Research and Development Center (U.S.) |
| Series/Report no.: | Miscellaneous paper (U.S. Army Engineer Waterways Experiment Station) ; N-68-9. |
| Description: | Miscellaneous paper Abstract: Stress, particle velocity, and acceleration data were obtained from a 140-ton nitromethane row-charge detonation in a saturated clay-shale. The charge row consisted of two 40- and three 20-ton spheres (first and fourth charges were 40 tons) extending S 11 W from the Pre-GONDOIA I Charlie crater on an 80-foot spacing (first charge 105 feet from crater center). The primary instrument line (stress and particle velocity gages) extended S 79 E from the center charge (G) with gage stations 100, 150, 200, 300, and 400 feet from G. Gage depths were 10 and 50 feet except the 400-foot station which was gaged at 50 feet only. Acceleration measurements were made on the slopes of the Pre-GONDOIA I Delta and Charlie craters and at the Control Point (CP). Peak stress measurements were higher than Pre-GONDOIA I data. As the charge-to-gage distance increased, the individual compressional waves from the various charges began to coalesce. The resulting stresses (coalesced wave) scale using combined charge weights and cube root scaling. Initial peak horizontal velocity compares well with Pre-GONDOIA I data. Similar to stress, velocities resulting from the coalesced shock front scale using cube root. A low-amplitude, long-duration acceleration was recorded at the Delta and Charlie craters. The fractured crater material filtered out the high-frequency, high-amplitude motions anticipated at the crater slope and lowered the average propagation velocities. CP accelerations compare well with predictions based on competent media. |
| Rights: | Approved for public release; distribution is unlimited. |
| URI: | http://hdl.handle.net/11681/6768 |
| Appears in Collections: | Miscellaneous Paper |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| MP-N-68-9.pdf | 1.55 MB | Adobe PDF |  View/Open |