Energy absorption performance of a new circular-triangular nested tube and its application as sacrificial cladding

摘要

A circular-triangular nested tube (CTNT) was proposed for dissipating impact or blast energy. Experimental studies on CTNT energy absorbers under a lateral quasi-static crushing load were first conducted to reveal their deformation modes, force-displacement responses, and energy absorption performances. In addition, the influences of the circular-tube thickness and triangular-tube shape on the energy absorption performances of CTNTs were also discussed. A new energy absorption parameter, average curvature change (ACC), was proposed for evaluating the influence of geometry on the performance of an energy absorber that dissipates energy through changes in its curvature; further, the optimum geometric performance of the proposed CTNT energy absorbers was demonstrated based on a comparison with other nested energy absorbers reported in extant literature. The blast responses of the CTNT energy absorbers used as sacrificial claddings were numerically studied. The numerical results clearly presented the deformation modes, blast load mitigation, and energy absorption performances of the sacrificial claddings. The deformation mode of a CTNT energy absorber used as sacrificial cladding under blast loading was significantly different from that under quasi-static loading because the inertial effect and energy absorption capacity of the CTNT energy absorber increased as the weight of the trinitrotoluene (TNT) charge was increased. Moreover, the transmitted force was found to be reduced by 50.1%-74.3% on employing the CTNT energy absorber as sacrificial cladding, and the reduction magnitude decreased as the TNT charge weight was increased.