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Show 11 however, as a result of Equation ( 21) and ( 26), U* AI/ must be replaced by v- . CONCLUSIONS It seems that this study describes rather well the observed phenomona; however quantitative values cannot be attributed because the hypotheses which were used for their analytical simplicity are only approximations. It is likely that the introduction of the number W\ , and the derived M which describe the plastic behavior of the snow, does not stray too far from reality. On the other hand, the hypotheses concerning the propagation of stress in the section on secondary stability should be received with more skepticism,- results from these hypotheses may entail a large factor of error. It must also be realized that it is difficult to procure experimental values of Tc , UJ , w\ etc. Measurements made in the upper or lower portions of an avalanche zone do not necessarily describe the mean values in the critical layers of the slab prior to release. In order to compare theory with experiment, it is necessary to measure and average the parameters of the very slab which is about to release! The slab would also have to represent the theoretical conditions that were chosen in this study: large, constant slope, and free from natural anchors. In view of these difficulties, it seems that this study, inexact as it is, may already exceed what can be determined by experiment. REFERENCES Haefeli, R. 1942 Schweizer archiv fur angewandte wissenschaft und technik, Heft 9- 12 Kollbrunner, C. Fundation und Konsolidation, Bd. I. |