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为了分析砂岩类无序介质在各种荷载作用下的连续破坏过程，本文提出了梁－颗粒细观模型。在此模型中，介质被离散为一系列的颗粒单元，这些颗粒单元均由弹脆性的梁单元联结。颗粒的力学行为由离散单元法和有限单元法确定。当某个梁单元所受应力超过其强度时，就随即将它从计算网络中剔除，以模拟介质的破坏行为。为了验证数值模型的可靠性，分别从破坏模式和荷载－位移曲线两方面与物理模型实验进行了对比，结果表明两者基本一致。此外，探讨了无序性对介质裂纹分布形式的影响，并用分维表述了裂纹分布与荷载强度之间的内在联系。
In order to analyze the continuous failure process of sandstone-like disordered media under various loads, a beam-particle model is proposed in this paper. In this model, the media is discretized into a series of granular units that are all joined by a fragile beam unit. The mechanical behavior of the particles is determined by the discrete element method and the finite element method. When the stress of a beam element exceeds its strength, it is immediately removed from the calculation network to simulate the destruction of the medium. In order to verify the reliability of the numerical model, a comparison is made with the physical model experiment from the failure mode and the load-displacement curve respectively. The results show that the two are basically the same. In addition, the influence of disorder on the distribution of medium cracks was discussed. The fractal dimension was used to describe the internal relations between crack distribution and load strength.