| Résumé | A series of 40 impact tests were conducted on large right circular cylinders (68.5 cm in diameter and 25.7 cm thickness) of iceberg ice collected from and iceberg in Labrador. The specimens were confines at the perimeter and base by a rigid metallic ring and plate. A spherically terminated impactor with center mounter pressure transducer, was dropped onto the flat top surface of specimens from various heights and with various added masses. Impact velocity varied from 1.8 to 3.9 m/s; impactor mass varied from 155 to 510 kg and the ice specimen temperature varied from -0.5 to -14.5°C. Peak center pressures averaged from about 40 MPa at the highest temperature to about 76 MPa at the lowest temperature, with the highest recorded pressure being 95 MPa. Crater volume increased with increasing impact energy, as expected, however the specific energy of the ejected materials was found to decrease as the energy impact and the crater volume increased. A mechanism for the observed behaviour is proposed. |
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