The performance of the sandwich plates with the hierarchical pyramidal core under impulsive loads is compared to that of the sandwich plates with the first order pyramidal core with the same weight. Two-type core geometries are considered: first order pyramidal truss and second order pyramidal truss. The 3D finite element models under impulsive loads are established by ABAQUS. The relationship between the displacement and the time of the two structures under impulsive loads with the same relative density and the same weight is analyzed. A limited study is carried out for the two core types with respect to the respective geometric parameters, including the dimensionless impulse and the relative density of the cores. The energy absorbility of the two structures are compared. Results show that the 80% inner energy in the structures comes from the plastic energy dissipation. With the increasing dimensionless impulse, the energy absorbility goes up and the impulse-resistance of the two structures becomes to be same when the dimensionless displacement holds on the line.%讨论了有着相同重量的一阶和二阶金字塔点阵结构在冲击载荷作用下的抗冲击和吸能性.用有限元分析软件ABAQUS建立了一阶金字塔芯体夹芯结构和二阶金字塔芯体夹芯结构在冲击戢荷作用下的三维有限元模型,分析了在冲击载荷下有着相同相对密度和相同体重的两种芯体结构的位移与加载时间的关系,比较了两种芯体结构随着无量纲冲量和相对密度增加时的抗冲击能力,并分析了夹芯结构的吸能机理及两种芯体结构的吸能能力.结果表明,两种芯体结构中储存内能的80％以上均来源于塑性能释放.随着无量纲冲量的增加,两种芯体结构的吸能率在增加,二阶金字塔芯体结构在无量纲位移趋于平缓后其吸能率和抗冲击性能与一阶金字塔芯体结构相接近.
展开▼
