基于分层一阶剪切理论的夹层梁弯曲特性.pdfVIP

第 17卷第6期 建 筑 材 料 学 报 Vo1．17．No．6 学兔兔 2014年12月 J0URNAL 0F BUILDING MATERIALS Dec．，2014 文章编号：1007—9629(2014)06—1049—06 基于分层一阶剪切理论的夹层梁弯曲特性 郝景新 ， 吴新凤 ， 刘文金 (1．中南林业科技大学 家具艺术设计学院，湖南 长沙410004； 2．中南林业科技大学材料科学与工程学院，湖南长沙410004) 摘要：为了构建夹层梁的弯曲位移模型，提出了一种基于二变量的分层一阶剪切理论，该理论满足 于Timoshenko梁平均切应变要求．然后，利用最小势能原理建立弯曲控制方程并用Rayleigh-Ritz 法求解．结果表明：由于考虑了上下表板抵抗剪力的能力，分层一阶剪切理论预测的跨中挠度比传 统夹层粱一阶剪切理论较为保守，用其计算的芯层切应变与切应力比传统一阶剪切理论低，但随 着芯层厚度的增加，两种理论的计算差异逐渐减小，通过分层一阶剪切理论反推出的剪力满足于 静力平衡条件． 关键词：夹层梁；Timoshenko梁；一阶剪切理论；分层理论；弯曲性能 中图分类号：TU531．1 文献标志码：A doi：10．3969／j．issn．1007-9629．2014．06．019 Bending Property of Sandwich Beam Based on Layer-Wise First—Order Theory HAO Jingxin ． W【，Xinfeng 。 L 己，Wenjin (1．College of Furniture and Art Design，Central South University of Forestry and Technology，Changsha 4 1 0004，China； 2．College of Material Science and Engineering，Central South University of Forestry and Technology，Changsha 410004，China) Abstract：A new simple layer—wise first—order theory(LFOT)with tWO variables was proposed，in which the shear strain was piecewise first-order function and integration of it through the laminate thickness could fulfill Timoshenko shear strain theory．The equilibrium equation was derived by minimum energy principle and solved by Rayleigh—Ritz method．After comparison with classical first—order theory(CFOT) and test results．it has been shown that the predicted value by LFOT is relatively more conservative than CF0T because of considering skin resistance to shear force．Generally，the core shear strain and stress cal— culated bv LFOT iS lower than that of CFOT with the same construction and loading leve1．But difference between