A damage model suggested by the Tuler–Butcher concept of dynamic accumulation of microscopic defects is obtained from experimental data on microcrack formation in synthetic kidney stones. Experimental data on appearance of microcracks is extracted from micro-computed tomography images of BegoStone simulants obtained after subjecting the stone to successive pulses produced by an electromagnetic shock-wave lithotripter source. Image processing of the data is used to infer statistical distributions of crack length and width in representative transversal cross-sections of a cylindrical stone. A high-resolution finite volume computational model, capable of accurately modeling internal reflections due to local changes in material properties produced by material damage, is used to simulate the accumulation of damage due to successive shocks. Comparison of statistical distributions of microcrack formation in computation and experiment allows calibration of the damage model. The model is subsequently used to compute fracture of a different aspect-ratio cylindrical stone predicting concurrent formation of two main fracture areas as observed experimentally.

中文翻译：

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冲击波碎石术中结石破裂的实验校准损伤力学模型

微观缺陷动态积累的 Tuler-Butcher 概念建议的损伤模型是从合成肾结石中微裂纹形成的实验数据中获得的。微裂纹外观的实验数据是从 BegoStone 模拟物的微计算机断层扫描图像中提取的，该图像是在将石头置于由电磁冲击波碎石机源产生的连续脉冲后获得的。数据的图像处理用于推断圆柱形石头的代表性横截面中裂纹长度和宽度的统计分布。高分辨率有限体积计算模型能够准确模拟由于材料损坏产生的材料特性局部变化而引起的内部反射，用于模拟连续冲击造成的损坏累积。计算和实验中微裂纹形成的统计分布的比较允许损伤模型的校准。该模型随后用于计算不同纵横比圆柱形石头的裂缝，预测实验观察到的两个主要裂缝区域的同时形成。