岩石断裂力学的亚临界裂缝扩展理论认为微裂缝扩展可导致岩石破碎,即岩石颗粒破碎具有时间效应。根据亚临界裂缝扩展理论,提出了考虑微裂缝扩展导致堆石颗粒破碎时间效应的数值流变模拟新方法,并进行了考虑颗粒不同典型破碎模式的单轴流变颗粒流数值试验。在对比数值与室内流变试验曲线的基础上,分析了数值流变过程中颗粒破碎情况与颗粒体内部结构发展过程等。研究成果表明,两种试验手段得到的堆石流变的发展趋势基本一致,由微裂缝扩展引起的颗粒延时破碎是堆石流变的主要原因之一,深化了对堆石料变形机制的认识。
Based on the theory of subcritical expansion of cracks, rockfill particles breakage with the time-dependent effect is caused by the extension of microcracks. Through a new way to simulate the rheological behavior of rockfill, a series of numerical uniaxial rheological tests are carried out by the three-dimensional particle flow code method, according to the theory of subcritical expansion of cracks. The simulation results are partially compared with the lab experiments, and good agreement has been achieved. The evolution of microscopic characteristics for rockfill samples and particles breakage are presented visually during the process of numerical rheology. The analytical results show that rheology is the main results of the delayed particles breakage caused by the extension of microscopic crack, which further develops the recognition of the rheological mechanism of rockfill.