? 倍力桥 倍力桥是?? 谢菲尔德大学工程师唐纳德·贝雷于二 战时期,为解决渡河的问题,利用预先设计好的钢架迅速组合而成的人工便桥。 倍力桥的力学原理: 上端的纵梁压在横梁上,横梁又压在相对一根纵梁上,上下两根纵梁夹住一根横梁,受压之后产生 …
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