Herein, fast fracture initiation in glacier ice is modeled using a Material Point Method and a simplified constitutive law describing tensile strain softening. Relying on a simple configuration where ice flows over a vertical step, crevasse patterns emerge and are consistent with previous observations reported in the literature. The model’s few parameters allows identification of a single dimensionless number controlling fracture spacing and depth. This scaling law delineates two regimes. In the first one, ice thickness does not play a role and only ice tensile strength controls the spacing, giving rise to numerous surface crevasses, as observed in crevasse fields. In this regime, scaling can recover classical values for ice tensile strength from macroscopic field observations. The second regime, governed by ice bending, produces large-scale, deep fractures resembling serac falls or calving events.

中文翻译：

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冰川破裂过程中机械控制和几何控制之间的过渡

在此，使用质点法和描述拉伸应变软化的简化本构定律对冰川冰中的快速破裂启动进行建模。依靠冰在垂直台阶上流动的简单配置，裂缝模式就会出现，并且与文献中报道的先前观察结果一致。该模型的几个参数允许识别控制裂缝间距和深度的单个无量纲数。该比例定律描绘了两种制度。在第一个例子中，冰厚度不起作用，只有冰的拉伸强度控制间距，从而产生许多表面裂缝，如在裂缝场中观察到的那样。在这种情况下，缩放可以从宏观现场观察中恢复冰抗拉强度的经典值。第二种情况由冰弯曲控制，产生大规模、深的裂缝，类似于冰塔坠落或崩解事件。