Finite element analysis of sandwich panels with longitudinal joints and large openings

Original scientific paper Lightweight structural sandwich panels made of two thin steel facings, which are bonded to a relatively thick and light insulating mineral wool core, are often used for wall claddings. The sandwich panel clad structures are frequently weakened by cut-outs and openings for doors, windows, and in other cases. If the resistance of remaining cross-section of a weakened panel is not sufficient an additional load-bearing support of adjacent panels through the longitudinal joints must be activated. The paper concerns effects of large openings on load-bearing capacity and structural stiffness of sandwich panel claddings. Since it is not possible to give generally acceptable rules to evaluate their complex structural behaviour at the present time this research project was conducted using finite element models to study the local and global behaviour for a certain sandwich panel product and a certain design examples. Firstly, a finite element model of double interlocking tongue and groove joint between neighbouring panels was built to study behaviour of the panel-to-panel connection. Secondly, finite element models of two typical design examples of sandwich panel claddings with large opening and load transfer from weakened sandwich panel through the longitudinal joints to the adjacent panels were built and analysed numerically. And thirdly, the laboratory experiment of two studied design examples was also conducted. The results obtained from the experiment were reasonably agreeable to support the finit