Determination of optimal coupling stiffness using modal updating techniques for a Stiffened Plates

Abstract Stiffened structures are often utilized as structural members for numerous applications in various fields of engineering like Civil, Automobiles, Naval, Aerospace, etc. Thus analyzing stiffed structure for their structural integrity become pivotal. Simplest instance of a stiffened structure could be a plate with a beam acting as a reinforcement. The presented study focuses on Modal analysis of a stiffened plate comprising of a base plate and a beam attached to it in the longitudinal direction. Numerical analysis is carried out by formulating a FE model for the beam and plate. The plate and beam elements are coupled using discrete spring element. The capability of the model is verified by comparing the natural frequencies obtained through experimental techniques. A numerical based model updating was carried out to determine the optimal spring stiffness using Latin hypercube sampling. The optimal values of the spring stiffness were determined which reduced the error in the natural frequencies.