Isogeometric Analysis of Laminated and Carbon Nanotube Reinforced Composite Stiffened Plate Using Higher Order Shear Deformation Theory

The current work first develops a thorough mathematical formulation for the isogeometric analysis of stiffened plates made of different advanced materials. The material configurations considered in present work include those of fiber reinforced laminated composites, carbon nanotube (CNT) reinforced composites (FG-CNTRC), besides simple isotropic homogeneous configurations as a special case. A higher-order shear deformation theory (HSDT), namely the semi-refined higher order shear deformation theory (SRHSDT7) due to Bhar (2011), is used for the mathematical formulations to focus the significance of transverse shear deformation for thick laminated composite stiffened plates. For the aforementioned kind of stiffened plates, a formulation for linear static and free vibration analysis has been developed. The developed mathematical formulation is implemented into a FORTRAN computer program developed inhouse. This computer program is then utilized to thoroughly validate the results generated by this for various analysis of bare (unstiffened) and stiffened plate problems available in existing literature. Further additional results for various geometric and material configurations, stiffener numbers and locations, boundary conditions are also presented as parametric studies. This paper presents the isogeometric analysis (IGA) based on SR-HSDT7 for the static and free vibration analysis of laminated composite and CNTRC stiffened plate. The same basis function is used by the IGA for geometric representation and numerical solution. The stiffener in CNTRC stiffened plates is distributed uniformly, however only one type of plate-FG-V, FG-O, and FG-X is functionally graded. The other type of plate is uniformly distributed (UD). The material properties of CNTRC plate are vary continuously along the thickness direction. Numerical examples are presented by increasing the number of stiffeners for different material configurations.