MODELING STRATEGY OF SANDWICH STRUCTURE WITH HETEROGENEOUS CORE UNDER IMPACT LOADING

• Main Author: Pratama, Valdo
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/68996
• Institution: Institut Teknologi Bandung

Sandwich composite structure (relatively a thick core inserted between two thin laminated composite faceplates) have been used to fabricate important components in aircraft structure, e.g. aileron, nacelle, etc. As these components are prone to either low or high-velocity impact due to tooling and equipment drop, runway debris, or bird strike, a method to improve their impact damage resistance is desirable. The recent method includes the replacement of classical honeycomb core with auxetic core, i.e. core that have Negative Poisson’s Ratio (NPR). It was found that under impact loading, the auxetic core produced an effective “densification” phenomena, and thus resulting in the localization of damage. However, the mechanism of core densification and localized damage phenomena in the sandwich structure is largely unknown, let alone damage dissipation level that is controlled by various geometrical parameters or mechanical properties of core and its faceplates. Besides that, a more fundamental knowledge in strategically model the sandwich structure with heterogeneous core, i.e. auxetic core, is also desirable to obtain modular knowledge when research requiring sandwich structures with heterogeneous core to be conducted will help and ease the working process. From the results we obtain, for starters, we can have a base for knowledge about strategical modeling on the numerical model and simulate a sandwich structure with a heterogeneous core. However, further improvement is needed. Moreover, phenomena that should occur in an auxetic heterogeneous core, such as core densification and localized damage when subjected to impact loads, can be seen in our work.