テーパー角変更によるサンドイッチパネルtapered end-closure結合部の初期損傷抑制

Abstract

For the configuration of the CFRP face plates/foamed plastic core sandwich panel joint, a tapered end-closure type joint is selected and studied. In this type of joint, the sandwich panel is tapered to form the solid laminate of two face plates near the joint portion and two panels to be joined are mechanically fastened at the solid laminate portions with a splice plate. This type of joint could be suitable for the aircraft panel joint configuration, because a flat surface can be obtained at the joint portion, which is advantageous in an aerodynamic point of view. However, in a previous study, it was reported on the results of tensile strength test that the delamination crack initiating from tapered core end and propagating through the interface between two face plates was observed as an initial failure mode at much lower tensile load compared to the final failure load. In this study, the angle of tapered panel portion is focused on and the initial failure suppression effect caused by the change of taper angle is investigated through experiment and numerical analysis. And it is found that the smaller taper angle is preferred to suppress the initial failure.