Dynamic and static ultimate bearing capacities of continuous double-beam plates considering interaction between plates and beams

Abstract

Over the past few decades, the majority of research has focused on the ultimate bearing capacity under static load. These beam plates may experience dynamic impact loads in some extreme conditions, hence ultimate bearing capacity of double-beam plate under quasi-static and impact loads, especially for dynamic static ratio of ultimate bearing capacity is very important to structural safety and lightweight design. A discrete method of the beam-plate coupled system is developed to analyse the dynamic and static ultimate bearing capacities of continuous double-beam plates with generalized constrained differential quadrature method in which the two square tube beams are parallel each other and connected with a rectangular plate continuously considering interaction between plates and beams. The contact forces between beams and plates are represented by a series of translational and rotational springs which can ensure the displacement compatibility between beams and plates. A series of tests of double-beam plates under quasi-static and dynamic loads is conducted to investigate the dynamic response and verify the proposed method. Additionally, the effects of the initial imperfection, width–thickness ratio, aspect ratio, rotational spring stiffness, impact time and peak load on dynamic and static ultimate bearing capacities as well as dynamic static ratio of ultimate bearing capacity are analysed. The study indicates that the ultimate bearing capacity of the double-beam plate under dynamic impact load is quite different from that of the double-beam plate under quasi-static load. The initial imperfection, peak load and impact time have a significant effect on dynamic static ratio of ultimate bearing capacity, while the effect of the edge rotationally-restrained spring stiffness can be ignored.