Abstract This paper proposes a 3D model for analyzing the rockfall trajectory within the framework of contact mechanics and rigid body dynamics, focusing on arbitrary shapes of the falling rock and terrain. Firstly, the sphericity and the concavity and convexity are defined to quantitatively describe the overall shape and local appearance of often-observed falling rocks, respectively. A generation algorithm is then proposed to generate falling rock and terrain with arbitrary shapes. The surfaces of the generated falling rock and terrain model are both meshed by triangular elements. A contact searching algorithm as well as a bilinear model for contact collision are presented to solve the interaction between the falling rock and terrain. Validated by available field test data, it is demonstrated that the proposed approach could simulate the four motion modes of rockfall such as falling, bouncing, rolling and sliding, as well as the transition between them.

中文翻译：

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考虑落石和地形任意形状的落石轨迹数值模拟

摘要 本文提出了一种在接触力学和刚体动力学的框架内分析落石轨迹的3D模型，重点关注落石和地形的任意形状。首先，定义了球形度和凹凸度，分别定量描述了经常观察到的落石的整体形状和局部外观。然后提出一种生成算法来生成任意形状的落石和地形。生成的落石和地形模型的表面均由三角形单元网格化。提出了一种接触搜索算法以及接触碰撞的双线性模型来解决落石与地形之间的相互作用。通过可用的现场测试数据验证，