通过缩比模型试验预测大型结构在冲击载荷下的响应,具有低成本、高效率、可实现性高的优点,随着轻质、高强度复合材料的广泛应用,冲击相似理论和缩放方法的研究变得越来越重要。对于弹性冲击响应下的层合板相似缩放问题,传统相似律受几何缩放比例和层合板铺层匹配的严格要求,几乎无法实现。本文基于定向量纲冲击相似律体系与弹性层合板本构方程,推导了弹性层合板的冲击相似律,得到了定向量纲描述的层合板刚度系数的相似比例关系,提出了一种通过调整缩比模型的铺层角度满足刚度协调、再通过调整冲击速度满足弹性层合板冲击响应相似的修正方法。数值算例结果显示,本文提出的弹性层合板冲击相似的缩放方法,在厚度畸变、厚度-材料畸变、厚度-材料-宽度畸变的情况下,均能够有效预测原型结构的冲击动态响应。
Using scale model experiments to predict the response of full-scale engineering structures under impact loads has the advantages of being economical, efficient, and feasible. As lightweight, high strength composite materials are widely used in large-scale aero-space structures, the study of the impact similitude theory and scaling methods for composite materials is becoming increasingly important. For the similarity scaling problem of elastic laminate under impact response, conventional scaling methods are limited by the strict requirements of layup configuration and scale factors in prototype structure, thus nearly impossible to achieve. This article combines the ODLV directional dimension impact similarity law system with elastic laminate constitutive equation, derives the impact similarity law of elastic laminates, and obtains laminate stiffness coefficient scale factors which de-scribed by the directional dimension. Based on the similitude relationship, a similitude distortion modified method was proposed: first adjusting the ply angles of scaled models to achieve stiffness compatibility, then modifying the impact velocity to achieve similarity in the elastic laminated plate impact response. Simulation results show that the scale models have good similarity with the prototype structure in displacement, impact force, and impact energy response, suggests that the designed scale model under the instruction of the laminate impact similarity scaling method proposed in this article can effectively predict the impact dynamic response of the prototype structure.