冲击载荷下受轴向约束的点阵材料夹芯简支梁

Impulsive loading of simply supported lattice truss core sandwich beams with axial restraints

对受到均布冲击载荷的轴向不可移点阵材料夹芯简支梁进行了刚塑性动力响应理论分析和弹塑性有限元分析.首先给出了夹芯梁在外包和内接屈服条件下中点最大挠度的理论预测值,并与有限元结果进行了比较,有限元计算结果介于两种屈服条件给出的理论预测结果之间,有限元计算的支座处最大转角与外包屈服条件给出的理论预测结果接近.然后考察了点阵材料夹芯梁的抗冲击性能和吸能效果.结果表明:夹芯梁的最大挠度和塑性耗散能对杆元与面板夹角及相对密度十分敏感,设计合理的夹芯梁具有很好的吸能效果和抗冲击性能.

The dynamic response of a simply supported lattice truss core sandwich beam with axial restraints subjected to uniform transverse impulsive loadings was studied through rigid-plastic analytical model and elastic-plastic finite element （FE） calculation. Firstly, the maximum deflections of the sandwich beam predicted by both circumscribing and inscribing yield loci were given and compared with those predicted by finite element method. It is found that the FE predictions of the maximum deflections are between those predicted by the circumscribing and inscribing yield loci. The FE predictions of the maximum angle of rotation at the simply supported ends approach the analytical model employing the circumscribing yield locus. Then the shock resistance and energy-absorbing capability of the sandwich beam were studied. According to the FE analysis, it is indicated that the maximum deflection and plastic energy absorption of the sandwich beam are sensitive to the relative density and inclination angle of the sandwich core member, and the properly designed sandwich beams have superior energy-absorbing capability and shock resistance.