近距空爆载荷作用下高韧钢的抗爆性能及影响因素研究

Study on the Blast-Resistant Performance and Influence Factors of High-Toughness Steel Subjected to Close-Range Air-Blasts

为探讨高韧钢的抗爆性能及其影响因素,结合空爆试验,对高韧钢平板和加筋板的动响应过程进行了数值模拟,并与相同厚度的高强钢进行了对比。首先,开展了高韧钢和高强钢平板的空爆试验,对比分析了2种材料平板的变形和破坏试验结果。随后,采用LS-DYNA非线性有限元程序对高韧钢平板在近距空爆载荷作用下的变形/失效过程进行了数值模拟,并与试验结果进行了对比,验证了数值模拟方法的合理性。在此基础上,通过数值模拟进一步分析了高韧钢平板和加筋板结构的动态响应过程和失效机理。研究结果表明,在TNT药量为1200 g、爆距为100 mm的近距空爆载荷作用下,10 mm厚的高韧钢平板仅发生拉伸大变形,而10 mm厚的高强钢平板中部出现大破口。高韧钢平板的抗爆性能明显优于同等厚度下的高强钢平板。近距离空爆载荷作用下,高韧钢平板的主要变形模式为整体拉伸变形,而高韧钢加筋板结构的主要破坏模式为沿加筋部位的剪切破坏。随着载荷强度的增大,高韧钢加筋板结构呈现出3种不同的失效破坏模式;随着加筋高度的增大,面板沿加筋的局部剪切应力更大,高韧钢加筋板的抗爆性能反而会劣化。研究结果展示了高韧钢的抗爆优势,可为高韧钢在舰船防护结构中的潜在应用提供技术支撑。

To study the blast-resistant performance and influence factors of high-toughness steel,dynamic response processes of high-toughness(HT)steel flat and stiffened plates were analyzed by numerical simulations and air-blast experiments.Firstly,air-blast experiments for both HT steel and high-strength(HS)steel flat plates were carried out.Comparisons of deformation and damage between HT and HS flat plates for experimental results were performed.Subsequently,deformation and failure processes of HT steel flat plates under close-range air-blast loading were analyzed by nonlinear finite element code LS-DYNA.The validity of numerical simulation method was verified by experimental results.On the basis of verification,the dynamic responses and failure mechanisms of HT steel flat and stiffened plates were further investigated by numerical simulations.Results show that under the close-range air blast of 1200 g TNT charge and 100 mm stand-off distance,the HT steel flat plate of 10 mm thickness only produces large stretching deformation,whereas the HS steel flat plate of the same thickness appears a big crevasse at its central region.To the same thickness,HT steel flat plates behave obvious superior blast-resistant performance.Under close-range airblast loading,HT steel flat plates mainly exhibit overall stretching deformation,whereas HT steel stiffened plates produce shear damage along stiffeners.As load intensity increases,three different failure modes occur for HT steel stiffened plates.The local shear stresses in the panel of the HT steel stiffened plate increase with the increase of stiffener’s height.This instead deteriorates the blast-resistant performance of HT steel stiffened plates.This study demonstrates the blast resistance superiority of HT steel,and can provide a technical support for the potential application of HT steel in warship protective structures.