脆性材料剪切过程的数值仿真与试验验证

乏燃料组件剪切是乏燃料后处理的关键步骤,但由于其具有较高的放射性,科研试验中常采用由不锈钢和脆性材料组成的模拟组件来替代。针对脆性材料采用Drucker-Prager模型与Shear Damage模型相结合建立剪切本构模型,并选取脆性材料的典型代表砂浆进行剪切试验验证,通过对砂浆基体块进行加载速度为5,20,30,40,50 mm/s的剪切试验,验证了数值模型的正确性。并研究了其弹塑性变形、裂纹萌生、裂纹扩展和断裂分离的全过程,以及过程中受力变形情况。研究结果显示剪切力随速度的增加在一定范围内波动,剪切力随间隙的增大呈现先增大后减小的趋势。

Numerical simulation and experimental verification of shearing brittle materials

The shearing of spent fuel assembly is a key step in the spent fuel reprocessing process. Due to the high radioactivity of spent fuel assembly, simulating assembly often combines brittle materials with stainless steel in shearing test research. In this study, Drucker-Prager model and Shear Damage model were combined to establish the shear constitutive model. As the typical representative of brittle materials, the mortar was chosen to be tested and the model was verified at the speed of 5, 20, 30, 40, and 50 mm/s. The experimental results matched with simulation well. Moreover, the shearing process of brittle materials were analyzed, including the elastic deflection, the plastic deflection and the breaking of the mortar. The results show that the shear force fluctuates in a certain range with shear speed increases from 5 mm/s to 50 mm/s, and the shear force first increases and then decreases with the increase of the tool clearance.