ABSTRACT
This chapter introduces the topic by presenting comparisons between computed and closed form solutions for some of the problems. In making these comparisons it considers only typical elements and nodes. The chapter presents formulation of two- and three-dimensional problems in a general sense. It considers different two-dimensional problems in this and subsequent chapters. The chapter desires torsion first because it involves only one degree of freedom or unknown at each point (node). It illustrates a number of formulation procedures: displacement, stress or equilibrium, and hybrid and mixed, which are based on the energy principles. It also considers discretization involving triangular elements; quadrilateral elements. The chapter utilizes the element has a bilinear distribution of the stress function as compared to the linear distribution within the triangular element. It prefers to use the displacement approach to define the stiffness matrix for the elements inside the bar. The chapter outlines the stiffness matrix with warping functions.
