A stress-driven local-nonlocal mixture model for Timoshenko nano-beams
A stress-driven local-nonlocal mixture model for Timoshenko nano-beams
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DOI：
10.1016/j.compositesb.2019.01.012
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发表时间：
2019-05-01
影响因子：
13.1
通讯作者：
Medaglia, Carlo Maria
中科院分区：
文献类型：
--
作者：
Barretta, Raffaele;Caporale, Andrea;Medaglia, Carlo Maria
提出了一种适定的应力驱动混合模型。该模型是一个凸的局部和非局部相的组合，并规避了一些问题的不适定性出现在应变驱动的Eringen样配方的结构纳米技术的兴趣。混合物的非局部部分是应力场和由尺度参数表征的双指数平均核函数之间的积分卷积。应力驱动的混合物是相当于一个微分问题，配备了本构边界条件，包括弯曲和剪切场。通过一种有效的分析策略，建立了选定边界条件和载荷条件下的Brachenko纳米梁的封闭解。数值结果表明，在尺度参数方面的硬化行为。
A well-posed stress-driven mixture is proposed for Timoshenko nano-beams. The model is a convex combination of local and nonlocal phases and circumvents some problems of ill-posedness emerged in strain-driven Eringen-like formulations for structures of nanotechnological interest. The nonlocal part of the mixture is the integral convolution between stress field and a bi-exponential averaging kernel function characterized by a scale parameter. The stress-driven mixture is equivalent to a differential problem equipped with constitutive boundary conditions involving bending and shear fields. Closed-form solutions of Timoshenko nano-beams for selected boundary and loading conditions are established by an effective analytical strategy. The numerical results exhibit a stiffening behavior in terms of scale parameter.