Results of Ground Motion and Airblast Measurements, Project Essex 1, Phase 1, Vol. 1 and 2

Four high-explosive charges were detonated in saturated soil to simulate employment of atomic demolition munitions. Two 10-ton charges were buried 12 meters deep, one stemmed and one with a small open hole; one 10-ton stemmed charge and one 8.5-ton unstemmed charge were at 6 meters. On each shot instruments measured shock propagation above the charge, shock stress and ground acceleration at one position at half-shot depth and at three shot-depth positions, ground-surface acceleration at four to five positions, shock pressure in the open holes of the unstemmed shots, and above-ground airblast at several distances. Ground-surface displacement was measured with high-speed photography. Peak stresses ranged from 0.05 to 3 kilobars. These measurements were made to provide information on effects of charge burial depth and stemming, as well as physical data that could be used to verify the hydrodynamic codes being used for numerical simulation of ADM explosions.