如果你把超过10%的水果放在一个堆叠的农产品展示中——要小心了。
杂货店里标志性的倾斜农产品陈列柜倒塌时可能会造成混乱。但是，在这个结构倒塌之前可以取出多少水果的问题却异常复杂。发表在12月的《物理评论E》上的一项新研究最终给出了答案。
智利安托法加斯塔大学的物理学家爱德华多·罗哈斯说，水果展示的崩塌是研究雪崩和山体滑坡动力学的一个很好的系统，因为它们相对简单。所有的物体都以一种非随机的、晶体状的形式排列，并且大小和形状大致相同——例如，不像山腰上的地球。这使得检查删除一个对象对整个结构的影响变得更加容易。
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Using computer simulations, Rojas and colleagues modeled fruit stacked at many different angles to identify when a collapse would never happen and when one would happen instantly. In between those extremes, the team?simulated what would happen to the integrity of the display when more and more fruit was removed.
about 10 percent of the fruit in a given display can be removed before triggering an avalanche, the simulations suggest. If 29 shoppers grabbed an apple from a stack of 300, the next shopper might want to put on a hard hat before plucking one for themselves.
“Their?simulations certainly seem to have some of the hallmarks of our everyday?experience,” says Arshad Kudrolli, a physicist at Clark University in Worcester, Mass. “It is a nice approach?and can be generalized easily.”
Rojas and colleagues next hope to simulate angled stacks of objects of different sizes that are randomly arranged, like piles of rocks that could lead to dangerous rockslides.
?
Reference
