金属泡沫填充薄壁圆管的轴压载荷-位移关系

将泡沫填充圆管的能量吸收视为泡沫与圆管两者之和,基于包含偏心率效应的直链塑性铰模型和Reddy等对Alexander模型的改进结果,对圆管的变形模式进行了更改,以此来反映管壁与金属泡沫之间的相互作用效应,导出了金属泡沫填充圆管的静、动态轴向平均压溃力的表达式.通过理论预测与实验的对比,发现理论预测偏低,但与实验曲线的趋势保持一致,比空管与金属泡沫的平均载荷之和略高一些.此外,泡沫填充圆管的平均压溃力随填充泡沫平台应力的增大而呈线性增加,与已有研究结果及实际情况一致,由此表明了模型的合理性.

RELATION OF LOAD AND DISPLACEMENT FOR THE METAL FOAM-FILLED TUBE DURING THE AXIAL COMPRESSION

The energy absorption of metal foam-filled tube was regarded as the sum of that of metal foam and tube. Based on the straight chain plastic hinge model including the effect of eccentricity and the improving results of Alexander model by Reddy and Wall, the deformation mode of tube was modified to reflect the effect of interaction between tube wall and metal foam. Then, the expressions for the mean crushing force of static and dynamic axial compression of metal foam-filled tube were derived. By the comparison between theoretical prediction and experiments, the results predicted theoretically were found to be lower than experimental curve but agree well in the tendency, and slightly higher than the sum of average loads of tube and metal foams. In addition, as the plateau stress of the filling foam increases, the average compressive load of foam-filled tube improves linearly. This is consistent with the existed results and actual situation, proving the rationality of the model in this paper.