The Development of Incompatible Finite Elements for Plane Stress/Strain Using Multivariable Variational formulation

다변수 변분해법에 의한 비적합 4절점 사각형 평면응력 및 평면변형률 요소의 개발

Two kinds of 4-node plane stress/strain finite elements are presented in this work. They are derived from the modified Hellinger-Reissner variational principle so as to employ the internal incompatible displacement and independent stress fields, or the incompatible displacement and strain fields. The introduced incompatible functions are selected to satisfy the constant strain condition. The elements are evaluated on several problems of bending and material incompressibility with regular and distorted elements. The results show that the new elements perform excellently in the calculation of deformation and stresses.