New unified failure model on evenly distributed reinforced concrete members with box section

It is urgently needed to describe the structural collapse process under extreme conditions to survive people. For reinforced concrete structures it is still a difficulty to describe the failure of reinforced concrete members under complex internal force combination, such as under axial forces, bending moment, shear forces, and torsion working together. In this paper, based on the traditional Nielsen model, a new unified failure model on reinforcement evenly distributed concrete members with box section under combined forces is introduced. The advantages of the proposed new model are to consider the dowel actions of reinforcements and reasonably to consider of the shear carrying capacity of concrete, especially when compression stress of concrete is in a high value. Finally, the theoretical results of the new model are compared with a series of experimental results of box section members. The comparison has verified that the new model is more accurate and feasible for the design and calculation of box section members.