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The substructuring method provides a suitable tool to conduct modal analysis of large and complicated structures. In this method the original structure is decomposed into simpler and smaller substructures, and the dynamic properties of the resulting substructures are first evaluated independently. The original structure’s dynamic properties are subsequently estimated by coupling the substructures’ dynamic results. In this procedure, the boundary conditions need to be imposed in such a way that the overall behaviour of the original structure is properly represented. Substructuring method can be used in different types of dynamic analysis. The focus of this paper is on the modal type of... 

One of the main problems in the airline industry is that many aircrafts of today's fleet are approaching their calendaring life, and it is impossible to buy new planes and supply previous ones for most of the companies. Therefore, in order to extend the life of these aged planes, some studies have been performed. The purpose of these studies is to discover the causes of aging and removing them. Repairing, replacement and reinforcing some elements of the structure are important parts of this procedure. This process is called aging. One of the requirements of aging technology is the examination of the structural response to the applied external loads and knowledge of the structural design.... 

Additive manufacturing enables fabricating lattice structures with tailored mechanical responses based on lattice materials. Full exploitation of such a possibility requires reliable and efficient mechanical analysis tools to be explored by topology optimization algorithms for designing the interior architecture of the structures to meet the desired mechanical behavior. However, detailed mechanical analysis of lattice-based structures using the conventional finite element approach is prohibitively expensive due to lattices’ complex and fine features that demand adopting very fine space discretization. As an alternative, equivalent models based on the homogenization principle have widely been... 

This research investigates the possibility of using the component mode synthesis (CMS) method in experimentation. It should be noted that the original idea for this project originated from an industrial problem. The main issue in this problem was the lack of sufficient equipment to conduct tests on very large structural modes and the high computational cost for their analysis. Therefore, a test platform was constructed using a scaled-down sample (approximately 1:25) with connections that closely resembled real connections. This assembly was then tested separately, and the results were compared with analytical analyses. After updating and correcting the model in several stages, the structure...