solved write the equation of motion for computing stiffness of linear elastic computing stiffness of linear elastic computing stiffness of linear elastic finite element stiffness a simply supported beam and a moving simply supported beam of span length computing stiffness of linear elastic column supported by springs computing stiffness of linear elastic computing stiffness of linear elastic computing stiffness of linear elastic computing stiffness of linear elastic computing stiffness of linear elastic solved problem a simply supported beam simply supported beam of span length direct stiffness matrix method