ICSS 12, Extended Abstract: Improved Failure Description for an analytical Dimensioning Approach for Inserts in Honeycomb Sandwich Elements

Abstract

To reduce the mass of connections and local load introductions on sandwich elements, the use of insert elements are popular to generate removable connections or local load introductions on sandwich elements, since they offer a superior lightweight potential over joints with bolted connections directly set into the sandwich. Yet, lightweight structures made of sandwich elements with fiber reinforced face sheets and honeycomb core are still limited to special applications. One reason is the lack of straightforward calculation as well as standardized testing methods just for the insert type with the best lightweight performance, the core connected (i. e. potted), through-the-thickness insert type. Since a permanent shear buckling in the cell walls around the insert occurs as first relevant damage, the shear stress progression around an insert is critical for its load carrying capability. In order to find a mechanical-analytical based dimensioning approach, the authors summarized available mechanical models, able to predict the shear stress state around punctual loads on sandwich elements. To reduce the mass of connections and local load introductions on sandwich elements, the use of insert elements are popular to generate removable connections or local load introductions on sandwich elements, since they offer a superior lightweight potential over joints with bolted connections directly set into the sandwich. Yet, lightweight structures made of sandwich elements with fiber reinforced face sheets and honeycomb core are still limited to special applications. One reason is the lack of straightforward calculation as well as standardized testing methods just for the insert type with the best lightweight performance, the core connected (i. e. potted), through-the-thickness insert type. Since a permanent shear buckling in the cell walls around the insert occurs as first relevant damage, the shear stress progression around an insert is critical for its load carrying capability. In order to find a mechanical-analytical based dimensioning approach, the authors summarized available mechanical models, able to predict the shear stress state around punctual loads on sandwich elements.