Coupling 2D continuum and beam elements: a mixed formulation for avoiding spurious stresses

Abstract This paper presents a novel approach to coupling beam and solid elements. Connecting standard elements with results in situation where the part of model covers cross-sectional deformation, while at assumptions only consider rigid body movement cross-section. Therefore, kinematic do not include cross-section deformations such as warping contraction. Due this restriction, spurious stresses occur transition zone. To circumvent problem, contribution introduces mixed hybrid element based on an extended Hu–Washizu functional. The extension allows contract warp. Compared other approaches that these phenomena, precomputation function is unnecessary. present considers deformation using local variables. On interface, there are displacement degrees freedom (depending discretization), whereas two one rotation. beam-like parts be replaced without affecting overall accuracy model. Besides solid–beam coupling, proposed formulation can also used apply boundary conditions well stress resultants interface. For sake simplicity restricting generality, underlying introduced for 2D linear elastic case. Numerical examples demonstrate causes no distributions part. full models compared beam–solid models.