柔性动边界梁在横向撞击下的动力响应

研究特定约束条件下梁受横向撞击的动力响应,这些约束表现为弹性支承刚度和阻尼特征,也就是具有柔性动边界.建立了具有动边界梁的力学模型,综合考虑弹性和阻尼支承、集中质量块以及支承不对称等情况.根据撞击局部区域的接触力—嵌入深度关系式,利用拉格朗日方法建立了横向撞击下柔性动边界梁的动力方程,并通过与简支梁在相同撞击条件下撞击力、横向位移的对比分析,说明了柔性支承对结构动力响应的影响.结果表明,低速撞击条件下,柔性支承对撞击力的影响较小,但对结构位移响应的影响较显著,并且弹性支承会使梁受撞击后的变形过程与简支梁相比增加一个变形阶段. 受横向撞击的动力响应,这些约束表现为弹性支承刚度和阻尼特征,也就是具有柔性动边界.建立了具有动边界梁的力学模型,综合考虑弹性和阻尼支承、集中质量块以及支承不对称等情况.根据撞击局部区域的接触力一嵌入深度关系式,利用拉格朗日方法建立了横向撞击下柔性动边界梁的动力方程,并通过与简支梁在相同撞击条件下撞击力、横向位移的对比分析,说明了柔性支承对结构动力响应的影响.结果表明,低速撞击条件下,柔性支承对撞击力的影响较小,但对结构位移响应的影响较显著,并且弹性支承会使梁受撞击后的变形过程与简支梁相比 加一个

Dynamic responses of beams with flexible supports subject to transversal impact

A metho d fo r dynamic responses o f beams was presented w ith specif ic co nst rained co ndition w hich appears as elast ic and damping feature, i. e. beams w ith flex ible suppor ts. T he mechanics model s of beams w ith f lex ible suppo rt s w er e established, and elast ic and dumping support s, lumped masses at the beams ends and non-symmet ric suppo rt s w ere taken account . Based on the formulae of the relatio nship betw een the co ntact fo rce and the embedding depth, the dynamic equat ions of beams w ith f lexible suppo rt s subject to tr ansv er sal impact w ere pro posed by use of Lag rang e metho d. The impact force and tr ansv er sal displacement of the beam w ith f lex ible support s w ere compared w ith those of simply suppo rted o ne under the same impact condit ions, w hich proves the inf luence of the flex ible support s on dynamic r espo nses. T he result s show that f lex ible support s have lit t le influence on impact fo rces but have notable inf luence on responses of displacement . Compared w ith simply suppo rted beam, a t ransformat ion stage o f the beam w ith elast ic support s under impact w as added.