Effect of large deflection on laminated composite plates

In this study, the effect of large deflection on the natural frequency of pre-stressed laminated composite plates with different lamination orientations is investigated. An external distributed vertical load is applied at the free edge of the plate when the other edge is clamped, and then the loading edge of the deflected plate is fixed without removing the load to model a pre-stressed curved plate case. The non - linear deflection curve of the large deflected laminated plate is obtained from the large deflection equation. The large deflection is lim ited to the deflection length corresponding to 25% of the plate length. The thin curved plate is modeled by employing the classical plate theory with a finite element analysis approach. Four different lamination orientations are used which are [0 degrees 0 degrees 0 degrees 0 degrees], [90 degrees 0 degrees 0 degrees 90 degrees], [0 degrees 45 degrees -45 degrees 0 degrees] and [0 degrees 90 degrees 0 degrees 90 degrees], which are used for the examination of large deflection. Besides, the natural frequency parameter of the present model, which is performed in MATLAB, is compared with ANSYS to verify the reliability and validity of the present model. The load parameter that forms the curved plate causes the different mode shapes for each lamination configuration.