Energy Dissipation in Structural Systems Containing MetallicTubular Elements

本研究项目包括以金属管为耗能元件的结构体系的准静力和冲击耗能特性的实验和分析研究。研究的具体目标包括以下五个任务。在任务1中，将根据管间边界条件、半径与壁厚比、应变硬化和应变率特性，对未加筋和加筋管组合簇的能量耗散特性进行优化。任务2是建立受冲击载荷影响的管道初始弹性响应的重要性，从而导致弹粘塑性响应。在任务3中，将研究非均匀管状坍塌模式。任务4将研究复合材料（泡沫填充）金属管在大变形条件下的行为。最后，Task 5将把之前NSF资助的研究中发展的一维结构冲击波理论推广到二维，并将其用于Task 1的冲击实验建模。这项研究将填补冲击力学领域的空白，并提供直接适用于开发更高效和有效的金属耗散系统的结果。这种系统在安全应用中具有挽救生命的潜力，在安全应用中，动能必须以受控的方式消散，使减速保持在允许的范围内。

The research program involves an experimental and analytical investigation of the quasi-static and impact energy dissipation characteristics of structural systems containing metallic tubes as energy dissipating elements. The specific objectives of the research include the following five tasks. In Task 1, the energy dissipation characteristics of clusters of unstiffened and stiffened tubular assemblies will be optimized with respect to their intertubular boundary conditions, their radius to wall thickness ratios, and their strain-hardening and strain-rate properties. Task 2 is concerned with establishing the importance of the initial elastic response of tubes subjected to impact loading resulting in an elastic-viscoplastic response. In Task 3, non- uniform tubular collapse modes will be studied. Task 4 will investigate the behavior of composite (foam-filled) metallic tubes under large deformation conditions. Finally, Task 5 will generalize the one-dimensional structural shock-wave theory developed in previous NSF funded research to two dimensions and employ it to model the impact experiments of Task 1. This research will fill a void in this area of impact mechanics and provide results directly applicable to the development of more efficient and effective metallic energy dissipating systems. Such systems have a life saving potential when employed in safety applications where kinetic energy must be dissipated in a controlled manner such that decelerations remain within allowable limits.