TY - JOUR AU - Glen, J.W. PY - 1955// TI - The creep of polycrystalline ice JO - Proc. R. Soc. Lond. A SP - 519 EP - 538 VL - 228 IS - 1175 AB - Polycrystalline blocks of ice have been tested under compressive stresses in the range from 1 to 10 bars at temperatures from –13°C to the melting-point. Under these conditions ice creeps in a manner similar to that shown by metals at high temperatures; there is a transient creep component and also a continuing or quasi-viscous component. The relation between the minimum observed flow rate , the applied stress σ and the absolute temperature T is = B exp ( -Q/RT) σn, where R is the gas constant, and B, n and Q are constants; the value of n is about 3.2, that of Q is 32 kcal/mole, and that of B is 7 x 1024 if the stress is measured in bars and the strain rate in years-1. At the higher stresses a third, accelerating stage of creep was observed; on the basis of the appearance and behaviour of sections cut from the specimens, this acceleration was attributed to recrystallization. The effect of changing the load during a test has also been studied; for large reductions creep recovery was observed. The results of these tests are discussed in connexion with previous work on metals and ice, and also with measurements of glacier flow. SN - 0080-4630, 2053-9169 UR - http://rspa.royalsocietypublishing.org/content/228/1175/519 N1 - exported from refbase (http://beta.refbase.net/show.php?record=17474), last updated on Fri, 01 Feb 2019 13:10:42 +0100 ID - Glen1955 ER -