Abstract In this paper, we develop a novel 3D computational method that describes the behaviour of rock bolts and rough rock-shotcrete interfaces as support systems. Specifically, a Finite Element model has been formulated and implemented using the user-defined element (UEL) subroutine with ABAQUS. The input parameters of the bolted cohesive model are determined experimentally. Once the location of the bolts is defined, the overall force-displacement performance of the system can be simulated. In addition, the rough interface is modelled as a combination of ‘bond’ and ‘Coulomb-friction’ laws where the cohesive stiffness reduces with degradation. To validate the model, we compared its outputs to the results of direct shear and bolt pull-out tests; a good agreement between the two approaches has been obtained. In addition, a mesh independent result is observed for the overall force-displacement response, which makes our model particularly fast and efficient. Furthermore, we conducted a parametric study by investigating the effects of number of bolts, bolt installation angle and pretension on the overall behaviour.

中文翻译：

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用于螺栓加固粗糙岩石-喷射混凝土界面建模的 3D 螺栓连接内聚元件

摘要 在本文中，我们开发了一种新颖的 3D 计算方法，该方法描述了作为支撑系统的岩石锚杆和粗糙的岩石-喷射混凝土界面的行为。具体来说，有限元模型已经用 ABAQUS 的用户定义单元 (UEL) 子程序制定和实现。螺栓内聚模型的输入参数通过实验确定。一旦确定了螺栓的位置，就可以模拟系统的整体力-位移性能。此外，粗糙界面被建模为“键”和“库仑摩擦”定律的组合，其中内聚刚度随着退化而降低。为了验证模型，我们将其输出与直接剪切和螺栓拔出测试的结果进行了比较；这两种方法之间已经取得了很好的一致。此外，观察到整体力-位移响应的网格独立结果，这使得我们的模型特别快速和高效。此外，我们通过调查螺栓数量、螺栓安装角度和预紧力对整体性能的影响进行了参数研究。