一种复合材料加筋夹芯板弯曲正应力工程计算方法

An engineering calculation method of bending normal stress for composite sandwich plate with stiffener

复合材料加筋夹芯板作为复合材料基本板架结构力学性能分析单元,是由夹芯板和加强筋组成,其蒙皮由不同厚度、不同材料和一定铺设角度的单层板叠合而成。利用材料力学理论和经典复合材料层合板理论,将蒙皮等效成正交各向异性层合板,推导一般情况下的复合材料加筋夹芯板中性轴位置控制方程,并采用等效截面方法,将加筋夹芯板截面等效成单一材料的组合截面,提出复合材料加筋夹芯板弯曲正应力的工程计算公式。复合材料加筋夹芯板各部分的最大弯曲正应力由模量比和距中性轴位置共同决定。本文提出的加筋夹芯板弯曲正应力工程计算方法,与有限元计算结果十分接近,主要弯曲正应力计算值与有限元值误差不超过10%,可以满足工程上的计算要求。此公式形式上和各向同性材料弯曲正应力的计算公式一致,给掌握复合材料板架结构应力水平带来方便。

Composite sandwich plate with Stiffener is the analysis unit of the basic plate frame structure for mechanical properties,including sandwich plate and stiffener,whose skin is composed of different materials and different lamina with a certain angle. Using the theory of mechanics materials and the classical theory of composite laminate,the shin is equivalent to orthotropic laminate,then deriving the generally control equation of neutral axis for the sandwich plate with stiffener. Employing equivalent section method,the section of sandwich plate with Stiffener is equivalent to compound section of a single material,then raising the bending normal stress engineering formula of sandwich plate with stiffener. The maximum normal bending stress of each part are determined by the modulue ratio and distance from the neutral axis.The engineering calculation method of bending normal stress is very close to the simulation value,the error of the main bending normal stress value between calculation value and simulation value is less than 10%,which meets the requirement of Engineering. It is formally consistent with isotropic material＇ s formula,which can bring convenience to master the stress level of composite plate frame.