爆炸荷载作用下结构冲量的测量

Measurement of Impulse Acted on a Structure Subjected to Blast Loading

冲击摆是间接测量爆炸荷载下瞬态冲量的一种有效装置。常用的冲击摆为典型的复摆模型,设计、加工和数据处理复杂,质心难以准确测定,对冲量测定的精度影响较大。特别是测量爆炸载荷试验中的冲量时,遇到较大的困难。文中引入一种冲击摆的改进装置,将传统的冲击摆简化为等效单摆,限制了传统冲击摆的转动效应,考虑了阻尼对冲量计算的影响,减小了不确定性因素产生的试验误差。对比分析两种冲击摆在爆炸荷载下冲量的测量原理,改进装置具有设计加工简单、试验精度高、数据处理方便等优点。最后将改进装置应用于泡沫铝夹芯壳的爆炸试验中,通过测量其最大平动位移得到了待测冲量,试验结果也证明了改进装置的可行性。

Ballistic pendulum is an effective set-up for indirectly measuring instantaneous impulse transferred to a blast-loaded structure. Typical impact pendulum is the physieal pendulum. It is difficult to accurately measure impulse transferred to a structure, especially in blast-loading experiment due to the fabrication error, complex mass center determination and data processing. A simplified single pendulum is proposed in this paper, which restricts rotational effect of traditional pendulum. It can also quantitatively describe the influence of damping to impulse. Comparing these two kinds of ballistic pendulums on the measuring principle of the impulse acted on a structure subjected to blast loading, the improved set-up is simpler, with higher precision and more convenience of data processing. Using this test set-up, the maximum displacement of an aluminum foam core sandwich structure was measured and the impulse transferred from blast loading was calculated. Results validate the feasibility of the improved set-up.