Within the framework of the planar cross-section hypothesis, the construction of calculation formulas for determining stresses and deformations in cross- sections of an elastoplastic member under conditions of planar transverse bending is considered. The rod material works according to a bilinear tensile pattern and resists both tension and compression equally. The cross-section of the member, which is constant along its length, has one vertical spine of symmetry. The condition of ultimate equilibrium of an elastoplastic rod is recorded. Calculation formulas for normal stresses on platforms in the cross-sections of the member, for shear stresses, for normal stresses on horizontal platforms when loading a member with a distributed load are given. curvature of the curved axis of the rod on the elastic and elastoplastic sections of the rod is determined. Differential equations of the curved axis of the rod on the elastic and elastoplastic sections of the rod are given. The residual normal and shear stresses are determined after the member has been completely unloaded. The differential equations of the curved axis of the member after it has been completely unloaded are recorded. The obtained design relations can find practical application in the design of an elastoplastic member from both the strength condition and the stiffness condition.