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As a first endeavour, nonlinear dynamic response of the glass fibre-reinforced​ epoxy (GRE) laminated composite cylindrical shells under an impulse load is investigated based on the first-order shear deformation theory (FSDT) of shells. Green's strain and von Kármán hypothesis are assumed to consider the geometrical nonlinearity due to large deformation in the model. A new solution procedure composed of the differential quadrature method (DQM) based on the direct projection of the Heaviside function and a non-uniform rational B-spline (NURBS) based multi-step time integration scheme is employed to discretize the governing equations in the spatial and temporal domains, respectively. The approach is validated by showing its fast convergence rate and performing comparison studies with available solutions in the limited available cases. A comprehensive parametric study is performed then on the model and the effects of the geometrical parameters, number of layers, load location, time durations, and types of impulse loading on the nonlinear dynamic responses of GRE laminated composite cylindrical shells are investigated. • Nonlinear dynamic response of cylindrical shells under impulse loading is studied. • Cylindrical shells are made of GRE reinforced composite layers. • FSDT theory and Hamilton's principle are employed to formulate the problem. • A new coupled DQ-Heaviside technique is presented to discretize spatial domain. • A NURBS based multi-step method is used for the solution of nonlinear ODEs. [ABSTRACT FROM AUTHOR]

In this paper, dynamic response of multilayer functionally graded graphene platelets reinforced composite (FG-GPLRC) cylindrical shells in thermal environment under an impulse load is studied based on the first order shear deformation theory (FSDT) of shells. The cylindrical shells under consideration are made up of multiple graphene platelet reinforced composite (GPLRC) layers with uniformly distributed and randomly oriented graphene platelets (GPLs) in each layer. GPL concentration is assumed to be graded in thickness direction. A new differential quadrature method based on direct projection of the Heaviside function is utilized to spatially discretize the governing equations. To solve the resulting system of ordinary differential equations (ODE) in temporal domain, a recently developed multi-step time integration technique, introduced based on the non-uniform rational B-spline (NURBS), is employed. After validating the approach, the effects of the different GPLs distribution patterns, the weight fraction and dimension ratios of the GPLs, temperature change, time durations and types of impulse loading on the dynamic responses of the FG-GPLRC shells are investigated and discussed. It is shown that the addition of only little GPLs to polymer matrix considerably decreases the period of oscillatory portions of the center deflection. • Dynamic response of cylindrical shells under impulse loading is studied. • Cylindrical shells are made of multilayer FG-GPLRC. • Presenting a new DQM based on direct projection of the Heaviside function. • The problem is formulated based on the first order shear deformation theory. • A multi-step NURBS-based method is used to discretize temporal domain. [ABSTRACT FROM AUTHOR]