Performance of bolted joints in discontinuous ceramic cored sandwich structures
Date
2010
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
University of Delaware
Abstract
Thick section composites that consist of discontinuous ceramic tile arrays as a core represent a unique class of sandwich structures. They have been developed to provide a balance of structural and impact performance at minimum weight. Bolted joints are often used to fasten the Discontinuous Ceramic Cored Sandwich Structures (DCCS structures) to the primary frame. Extensive experimental testing has been completed in order to better understand the performance of bolted joints in DCCS Structures. In this study specimens with 0.5 inch pins are subjected to in-plane tensile loading statically to establish the sequence and severity of failure modes that occur in the tiles, face sheets and the bonding interlayer. Static testing was completed on various geometric ratios such as pin spacing and edge distance as well as the influence of tile gaps that exist in the discontinuous tile array. Specimens were also subjected to in-plane tensile fatigue loading to determine the fatigue sensitivity of the joints in the DCCS structure. This study provides a better understanding of load paths from the pin into the face sheets and ceramic tiles, the material’s failure modes, and the sequence and load levels at which these failures occur for both static and fatigue loading conditions. The compilation of data determined from this study will result in design guidelines assisting engineers in future design of bolted joints in DCCS structures.