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為了研究重復沖擊載荷作用下泡沫金屬夾芯梁的動態響應,采用Abaqus數值仿真軟件,基于可壓碎泡沫模型（crushable foam）,建立了泡沫金屬夾芯梁遭受楔形質量塊沖擊的有限元模型。通過將仿真獲得的夾芯梁上下面板最終撓度與重復沖擊實驗結果進行對比,驗證仿真方法的準確性。在此基礎之上,分析了泡沫金屬夾芯梁在楔形質量塊重復沖擊作用下的變形模式、加卸載過程以及能量耗散特性。結果表明,在重復沖擊載荷作用下,夾芯梁的變形不斷累積,上面板主要出現局部凹陷和整體彎曲,而芯層則是局部壓縮,下面板表現為整體彎曲。在重復加卸載過程中,加卸載剛度隨著沖擊次數的增加而增大。隨著沖擊次數的增加,上面板和芯層的能量吸收增量不斷減小,而下面板的能量吸收增量不斷增加,且最終均趨于穩定。泡沫金屬夾芯梁的塑性變形能增量不斷減小,而回彈系數隨著沖擊次數逐漸增加,最后趨于穩定值。 The phenomena of repeated impacts are very common, especial in the field of ship and ocean engineering. When the ship structures suffering from repeated impact loadings, the deformation and damages will accumulate, leading to failure even damage of the structures, which may cause serious accident. In order to study the dynamic behaviors of metal foam sandwich beams (MFSBs) under repeated impact loadings, the nonlinear finite element model was established based on the material model of crushable foam by using Abaqus-Explicit, and the approach to achieve repeated impacts in the software was proposed. The accuracy of the numerical simulation was verified by comparing the permanent deflections of front and back face sheets. Based on the results of the numerical simulations, the deformation modes, loading and unloading process as well as the energy absorption behavior of the MFSBs under repeated impacts were analyzed. Results show that during repeated impacts, the deformation of the MFSBs is accumulated gradually, the front face sheet mainly experiences global bending and local indentation, and the metal foam core suffers from local compression, while the back face sheet is subjected to global bending. During the repeated impacts, the loading and unloading stiffness increases with the impact number. The energy absorption of front face is larger than that of back face and metal foam core in all the impacts. As the impact number increases, the energy absorbed by front face sheet and foam core declines gradually, while that of the back face sheet increases, approaching a constant value. The plastic defo