Numerical Study and Experimental Validation of Dynamic Characteristics of Delaminated Composite Flat and Curved Shallow Shell Structure

In this paper, the transient behavior of an internally damaged laminated composite plate and shell structure under the influence of different mechanical loading types and constraint conditions has been analyzed numerically. For the numerical purpose, two well-known higher-order displacement kinematics are used to model the doubly curved shell panel in association with the finite-element steps. In addition, the internal delamination is modeled with the help of two sublaminate approaches including the intermittent continuity condition to obtain the necessary solutions. Further, the domain has been discretized with the assistance of a biquadratic nine-noded quadrilateral element. The panel motion equation is derived by integrating the total Lagrangian expression and solved to evaluate the time-dependent responses via an in-house computer code in association with Newmark's direct integration scheme. The stability of the found numerical solutions are checked through a convergence test and compared with established benchmark solutions. The performance of the developed numerical models are established by comparing the results with the subsequent experiments. Finally, the effect of internal debonding (size, position, and location) and other design parameters on the time-dependent deflections of the delaminated composite panel are examined including the geometries (spherical, cylindrical, elliptical, and hyperboloid) and discussed in detail. (C) 2017 American Society of Civil Engineers.