The beam-column connection is a fundamental element in frame structures and requires special attention in the calculation of the forces passing through it and the corresponding modeling. Often the joint is assumed to be rigid, but this does not correspond to the real behavior of the beam-column connection, as well as the real response of the frame structures. For the study of the moment-resisting frame in the leading countries in seismic research, uniform procedures have been introduced. However, in their seismic codes, there is still a discrepancy in how the shear force is determined in the beam-column connection.
In the present paper, a new mathematical model is proposed for the analytical determination of the forces passing through the joint in the beam-beam and column-column direction. The occurring large deformations in the beam and the column, which can be realized during an earthquake, are take into account. The material is elastic. The tensile/compressive stiffnesses and the bending stiffnesses were taken into account after superposition of the stiffnesses of the various materials making up the cross-section.The obtained values are compared with results determined by mathematical procedures proposed in other literature sources. The results show values of the shear force determined by the new model about 20% greater than those available in the literature.