Departamento de Física, Facultad de Ciencias, Universidad de Navarra, 31080 Pamplona, Spain.
Phys Rev Lett. 2012 Aug 10;109(6):068001. doi: 10.1103/PhysRevLett.109.068001. Epub 2012 Aug 7.
We present experimental and numerical results regarding the stability of arches against external vibrations. Two-dimensional strings of mutually stabilizing grains are geometrically analyzed and subsequently submitted to a periodic forcing at fixed frequency and increasing amplitude. The main factor that determines the granular arch resistance against vibrations is the maximum angle among those formed between any particle of the arch and its two neighbors: the higher the maximum angle is, the easier it is to break the arch. On the basis of an analysis of the forces, a simple explanation is given for this dependence. From this, interesting information can be extracted about the expected magnitudes of normal forces and friction coefficients of the particles composing the arches.
我们提出了关于拱结构对外界振动稳定性的实验和数值结果。相互稳定的颗粒二维串进行了几何分析，然后在固定频率和增加振幅的情况下进行周期性激励。决定颗粒拱抵抗振动的主要因素是拱中任意一个颗粒与其两个相邻颗粒之间形成的最大角度：最大角度越高，拱就越容易被破坏。基于对力的分析，对这种依赖性给出了一个简单的解释。由此，可以提取出关于组成拱的颗粒的法向力和摩擦系数的预期大小的有趣信息。
