Non-linear plastic analysis of steel arches under lateral buckling

Curved graphs are proposed that relate the shape of the box cross-section of an arch to the real ultimate lateral strength for various values of length, support conditions and of height of the cross-section.The real ultimate lateral strength of a series of arches is determined and the results obtained are then compared to those provided by Sakimoto and Komatsu [1].Elastic–plastic steel material and geometric non-linearity hypotheses, residual stresses, and initial lateral deflection are all taken into consideration with respect to the real ultimate lateral strength.

Research highlights
► a = b/h − qu/qp curves show a progressive increase of qu/qp with the “a” increase.
► In hinged arches a ≥ 1.50 collapse under uniform load is due to in-plane buckling.
► In clamped arches a ≥ 2 collapse under uniform load is due to in-plane buckling.
► If 90 ≤ L ≤ 180 m, the best improvement outside the plane is for a = 1.25.