Review article

The paper considers the issues of calculating complex steel-reinforced concrete beams by the limit states on the basis of the nonlinear diagram of concrete deformation ε-σ. Sargin`s formula normalized in Eurocodes and Russian norms is taken as a reference diagram. A comparison is made with the calculation for the formation of an ideal plastic hinge. There are pointed out significant discrepancies (up to 11%) in some calculation cases. The possibility of using the proposed formulas for calculating conventional reinforced concrete beams of complicated cross-section is indicated.