Abstract Soft solids undergo stick-slip instability which is characterized by the velocity weakening effect where interfacial shear stress decreases with sliding velocity. Soft solids show the hysteresis of energy release rate (G) during the stick and slip phase of a stick-slip cycle. In the present study, the effect of specimen thickness on G is studied by conducting the direct shear sliding experiments on gelatin hydrogel and glass substrate. Interfacial shear stress and corresponding crack lengths obtained during the slide-hold-slide (SHS) experiments are used to determine G analytically. Significance of specimen thickness, normal stress, gelatin concentration and sliding velocity on the hysteresis of G during a stick-slip cycle is discussed in detail. Increase in the specimen thickness, normal stress and gelatin concentration lead to an increase in the hysteresis of G as well as tendency of stick-slip instability. However, increase in the sliding velocity leads to decrease in hysteresis.

中文翻译：

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试样厚度、明胶浓度、法向力和滑动速度对明胶水凝胶粘滑振动影响的研究

摘要 软固体发生粘滑不稳定性，其特征是速度减弱效应，其中界面剪应力随滑动速度减小。软固体在粘滑循环的粘滑阶段显示能量释放率 (G) 的滞后。在本研究中，通过对明胶水凝胶和玻璃基板进行直接剪切滑动实验，研究了试样厚度对 G 的影响。在滑动保持滑动 (SHS) 实验期间获得的界面剪切应力和相应的裂纹长度用于分析确定 G。详细讨论了试样厚度、法向应力、明胶浓度和滑动速度对粘滑循环过程中 G 滞后的意义。增加试样厚度，法向应力和明胶浓度导致 G 的滞后增加以及粘滑不稳定的趋势。然而，滑动速度的增加导致滞后减小。