Overcoming two inherent limitations presented by the standard bonded‐particle model (BPM), the flat‐jointed model still lacks extensive application. This study hereby conducts a comprehensive investigation on the application of the flat‐jointed model in rock mechanics study. First, after a careful examination on the mechanical behavior of the flat‐joint contact, a systematic calibration has been conducted to build numerical models matching the mechanical properties of Carrara marble. Second, the validated model is used to simulate the fracturing behavior of marble specimens containing a single or en‐echelon flaws. Finally, the appearance of particle flow code (PFC) models has been compared with the results obtained from optical observation in order to establish a possible correlation between PFC models and real marble regarding microcracking behavior. Discussions suggest that to remove the particle size effect, the model resolution (ratio of sample dimension to the average particle diameter) should be larger than 30 in the flat‐jointed model and 150 in the BPM, respectively. Results from the above investigations suggest that the flat‐jointed model is capable of matching both the mechanical properties and fracturing behavior of Carrara marble. The numerical model is more reliable to predict the fracturing path at the instant of initiation than at failure. Development of initial fractures is not only controlled by the magnitude of tension force but also influenced by the extent of distribution of tension force. The appearance and components of a fracture in flat‐jointed models probably reveal not only its property (tensile or shear) but also the corresponding microcracking behavior of real rocks.

中文翻译：

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用平缝模型研究卡拉拉大理石的力学性能和断裂行为

克服了标准键合颗粒模型（BPM）提出的两个固有局限性，扁平连接模型仍然缺乏广泛的应用。因此，本研究对平缝模型在岩石力学研究中的应用进行了全面的研究。首先，在仔细检查平接头的机械性能后，进行了系统的校准，以建立与卡拉拉大理石的机械性能相匹配的数值模型。其次，使用经过验证的模型来模拟包含单个或梯形缺陷的大理石试样的断裂行为。最后，为了确定PFC模型与真实大理石之间的微裂纹行为之间可能存在的相关性，已将粒子流代码（PFC）模型的外观与光学观察结果进行了比较。讨论表明，要消除粒径影响，平接头模型的模型分辨率（样品尺寸与平均粒径的比）应分别大于30和BPM为150。以上研究结果表明，平缝模型能够匹配卡拉拉大理石的力学性能和断裂行为。数值模型在开始时预测破裂路径比失效时更可靠。初始裂缝的发展不仅受拉力大小的控制，而且还受拉力分布程度的影响。平缝模型中的裂缝的外观和组成可能不仅揭示了其性质（拉伸或剪切），而且还揭示了真实岩石的相应微裂纹行为。