VIBRATION RESPONSE OF MULTIFUNCTIONAL SANDWICH COMPOSITES APPLICABLE IN COMMERCIAL MOTOR VEHICLES

摘要

Sandwich composites are finding increasing use in transportation, aerospace, marine and commercial structures because they offer high bending stiffness and lightweight advantages. The traditional applications (aerospace, marine and rail/ground transportation) of sandwich structures primarily utilize polymeric foams and honeycomb as core materials. A limitation of traditional sandwich configurations is that the space in the core becomes inaccessible once the facesheets are bonded in place. This work considers the use of modular multifunctional lightweight composite sandwich structure(s) to retrofit existing critical areas of passenger compartments, driver cabins and cargo containers. In multi-functional sandwich composites the core or the facesheets are designed to incorporate functions such as sound / vibration damping, ability to route wires or embed sensors. The vibro-acoustic response of such multi-functional materials has received little attention and is an important issue when the structure witnesses dynamic impacts, blast and other unforeseen threats. In the present study the vibration response (in terms of natural frequency and damping) of sandwich composites with multi-functional features where the core is space accessible is investigated. The effect of damage induced by flexural loading on the vibration response is also investigated.