Structural optimization and sensitivity analysis using finite element force method

The objective of the present research is to develop a computer aided environment for optimization of structures by integrating the structural and design sensitivity analysis using the finite element force method, and mathematical programming techniques. A reliable tool for sensitivity analysis is perquisite for performing interactive structural design, synthesis and optimization. The sensitivity analysis is used to provide the gradient information to the gradient-based optimization algorithm. The developed structural optimization methodology using the force method is used to optimize discrete structures subjected to stress, displacement and frequencies constraints, and results are compared with those generated from displacement method and those in literature. The improved accuracy and efficiency of the developed optimization algorithm using analytical sensitivity analysis is also demonstrated by comparing the results with those obtained from the numerical sensitivity analysis.;Later, the developed optimization methodology is extended to the design of the stiffened panels subjected to uniform uniaxial compression loading. The buckling characteristic of stiffened panels subjected to uniform in-plane loading is of considerable importance, while designing for the aerospace, naval and civil engineering applications. The finite element model for the linear buckling analysis of the eccentrically stiffened panels based on the force method is developed, and is validated by extensive numerical analysis. The explicit expressions of the sensitivity of the buckling load with respect to dimensions of plate and stiffener are formulated, and integrated with the optimization algorithm and finite element analysis. The developed optimization algorithm is used to design different types of stiffened panels.