The dynamic behavior, including pulse buckling, damage initiation and delamination growth of slender fiber-reinforced plastic (FRP) laminated beams, having initial geometric imperfections, subjected to an axial impulse was investigated numerically and experimentally.; The dynamic equilibrium equations of slender FRP beams, having initial geometric imperfections were established based on the Timoshenko beam theory, with the consideration of several parameters such as the beam's axial and transverse inertia, transverse shear deformation, and the cross section rotational inertia. The von-Karman nonlinear strain-displacement relationship was used to describe the beam's response. The First-Order and Higher-Order Shear Deformation Theories were used to model the displacement fields of the beams. The dynamic differential equations were solved with the finite difference method. The results obtained from the proposed formulations agree well with those of the finite element analysis.; Pulse buckling, as an instability form (that is, the excessive growth of lateral, or out of plane displacement) can result from a single transient pulse load with a magnitude greater than that of the static Euler buckling load. Several parameters were investigated to assess the effects of initial geometric imperfection, slenderness ratio, curvature and boundary conditions of the beams on its pulse buckling response. A criterion for establishing the onset of the dynamic pulse buckling of the beams was also suggested.; The investigation of dynamic damage behavior of laminated beams was also carried out for understanding the damage initiation mechanism in the beams impacted axially by a moving mass. Hashin's failure criteria was used to predict the likelihood of damage generated in the beams. The experimental work was conducted using a horizontal linear bearing impact setup. Scanning Electron Microscopy was used to analyze the damage mechanism of laminated beams. The influence of fiber angle, lay-up sequence and initial imperfection on the critical energy required for damage initiation was also investigated.; Delamination propagation characteristics of the beam were also investigated numerically and experimentally. Carbon fiber/epoxy specimens with different initial delamination length, located along beams' length and through their thickness, were experimentally tested and numerically analyzed. The strain energy release rate based on the virtual crack closure technique (VCCT) was calculated at the tip of the delaminations. Critical impact energy for delamination growth was predicted numerically as well.; The dynamics pulse-buckling response of carbon/epoxy and E-glass/epoxy laminated composite beams with [(+/-67.5)n] s angle lay-up, subject to axial impact was investigated experimentally and numerically as well. These beams exhibited plasticity like response under axial impact.
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