Effect of trapezoidal pattern on deflection of sandwich panel with corrugated core

Abstract

The deflection behavior of square sandwich panels with corrugated core of trapezoidal cross section at different pitch lengths and heights of trapezoidal pattern was investigated using the FEM analysis, where the panel size was fixed at total height of 13.6 mm and panel side length of 600 mm. FEM analysis was performed under the condition that four sides were fixed and uniformly distributed load was applied. With decreasing the pitch length, the panel deflection decreased. At extremely short pitch length, the panel deflection increased with decreasing the pitch length because the conversion of the external load into the shear force became ineffective by small amount of bonding area. On the other hand, with increasing the pattern height, the panel deflection increased. This behavior of deflection could be approximated by Gompertz curve, and the suppressive factor of deflection was considered to be the inclination angle of trapezoidal pattern. The larger the bonding width, the higher the inclination angle and the lower the pattern height of the inflection point. Moreover, with increasing the pattern height, the weight ratio of the panel decreased. This is because the reduction in the weight of the panel due to the thickness reduction is greater than the effect of increased deflection due to the increased pattern height. The product of panel deflection and weight ratio became minimal at a given pattern height. This suggests adaptability to weight reduction needs or stiffness needs by selecting the appropriate pattern height, and the compatibility for both needs can be met at the minimal point.

Keywords

• sandwich panel
• corrugated core
• trapezoidal pattern
• pattern pitch
• pattern height
• deflection
• fem