复合材料加筋板低速冲击损伤及剩余压缩强度试验研究

采用落锤法对复合材料加筋板进行了低速冲击损伤（LVI）试验，根据复合材料加筋板构型，设计了冲击支持支架，研究了支持支架的间距对冲击结果的影响；用相同的冲击能量对复合材料加筋板结构中3处典型位置进行冲击，得到不同位置的损伤形貌；分别对完好件和损伤试验件进行压缩试验，将试验结果进行对比，分析不同位置的冲击损伤对结构压缩性能的影响。试验结果表明：在相同的冲击能量下，支持支架间距越小，所造成的冲击损伤越严重；在50 J冲击能量下，筋条区蒙皮处的冲击所造成的损伤不易观察，筋条间蒙皮处的冲击所造成的损伤最为明显，而筋条边缘蒙皮处的冲击可以导致筋条边缘的脱粘；冲击损伤会使加筋板屈曲载荷轻微下降，筋条间蒙皮和筋条区蒙皮冲击损伤对压缩结果影响相对较小，筋条边缘处的冲击会引起损伤处蒙皮的子层屈曲，并影响结构破坏形式，使结构压缩承载能力有较为明显的下降。

Experimental research on low-velocity impact and residual compressive strength of composite stiffened panels

Drop hammer low-velocity impact(LVI) tests on composite stiffened panel were carried out. Impact support bracket was designed based on specimen configuration, and effect of bracket pitch on impact damage was studied. Impact tests with the same energy on three typical positions of specimen were carried out to obtain the damage appearance. Compressive tests were conducted and test results of damaged specimens and undamaged ones were compared to analysis the effect of impact position on the compressive performance of the structure. Test results show that, with the same impact energy, the smaller the bracket pitch is, the severer the impact damage is. With the same impact energy of 50 J, damage on the stiffener skin is almost invisible, and damage on the skin between stiffeners is clearly visible, while impact on stiffener edge skin can result in debonding of the stiffener flange. Impact damage can slightly reduce the buckling load of the structure. The impact damage on the skin between stiffeners or on the stiffener skin has little effect on the compressive performance, while impact on stiffener edge skin can induce local buckling of damaged skin, and it has a notable effect on the failure pattern as well as the ultimate strength of the structure.