This work develops a continuum-based combined finite–discrete element method (FDEM) in the framework of the explicit finite element method in conjunction with fracture algorithms. To account for complex fracturing processes, both shear failure and tensile failure criteria are implemented. Furthermore, to investigate the effect of different fracture algorithms on the accuracy and computational efficiency of simulations, both the inter-element and intra-element fracture algorithms are developed in the continuum-based framework. Then, they are compared by two benchmark tests, of rock: the Brazilian tests and uniaxial tension tests. Besides, uniaxial compression tests under different loading rates are carried out to demonstrate the shear failure criterion and the corresponding fracture algorithm.The simulation results converge with the decrease of element sizes in the inter-element fracture algorithm. The intra-element fracture algorithm is proven to be more efficient and accurate in the simulation of fracturing processes compared to the inter-element fracture algorithm.

这项工作在显式有限元方法的框架内结合断裂算法开发了一种基于连续体的组合有限离散元方法 (FDEM)。为了解决复杂的压裂过程，实施了剪切破坏和拉伸破坏标准。此外，为了研究不同断裂算法对模拟精度和计算效率的影响，在基于连续体的框架中开发了单元间和单元内断裂算法。然后，它们通过两个岩石基准测试进行比较：巴西测试和单轴拉伸测试。此外，还进行了不同加载速率下的单轴压缩试验，以证明剪切破坏准则和相应的断裂算法。模拟结果随着单元间断裂算法中单元尺寸的减小而收敛。与单元间裂缝算法相比，单元内裂缝算法在压裂过程的模拟中被证明更有效和准确。