In this study, we present a new 2D numerical model, UBO-Inter, able to simulate the motion of a body sliding down a generic surface. Such a body is represented as a mechanical system of a finite number of point masses, where the points can be viewed as the projections on the sliding surface of the centers of mass of the elements which the system is discretized into. The masses are strictly adherent to the surface and interact with the neighbor masses through internal forces. The entire system can be seen as a 2D irregular grid where the masses occupy the nodes of the grid, and each grid side connects a pair of interacting masses. The external forces acting on the masses are gravity, which is the driving force, the reaction force of the sliding surface, the basal friction and the drag exerted by the environmental fluid (typically water, for a slide moving partially or totally underwater). The system is governed by a set of differential equations that are solved through a fourth-order Runge–Kutta scheme. After providing the formulation of the problem and a simple example admitting an exact solution that serves to illustrate the internal forces, we validate the model on the 1783 Scilla (Calabria region, Italy) landslide, that is a well-known catastrophic event that caused a lethal tsunami killing more than 1500 people. This case has been already widely studied and thus can be used as a benchmark for landslide models. The outputs of the model UBO-Inter in terms of time-histories of point-mass velocities, run-out and final deposit, are found to be in agreement with observations and with results published in literature and obtained through different numerical techniques.

中文翻译：

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滑坡建模的新方法：在意大利南部 Scilla 1783 海啸滑坡中的应用

在这项研究中，我们提出了一种新的 2D 数值模型 UBO-Inter，能够模拟身体从通用表面滑下的运动。这样的物体被表示为有限数量点质量的机械系统，其中这些点可以看作是系统被离散化为的元素的质心在滑动面上的投影。质量严格附着在表面上，并通过内力与相邻质量相互作用。整个系统可以看作是一个二维不规则网格，其中质量占据网格的节点，每个网格边连接一对相互作用的质量。作用在质量上的外力是重力，它是驱动力、滑动面的反作用力、基础摩擦力和环境流体（通常是水、用于部分或完全在水下移动的幻灯片）。该系统由一组通过四阶龙格-库塔方案求解的微分方程控制。在提供了问题的表述和一个简单的例子后，我们承认了一个用于说明内力的精确解，我们在 1783 年 Scilla（意大利卡拉布里亚地区）滑坡上验证了模型，这是一个众所周知的灾难性事件，导致了致命的海啸造成 1500 多人死亡。这个案例已经被广泛研究，因此可以用作滑坡模型的基准。发现 UBO-Inter 模型在点质量速度、跳动和最终沉积的时间历程方面的输出与观察结果和文献中发表的结果一致，并通过不同的数值技术获得。