Collapse Analysis of Planar Composite Frame under Impact Loads

Concrete filled steel tubular (CFST) structure has been widely used in construction practices due to its superior performances under various loading conditions. However, limited studies are available when this type of structure is subjected to impact or explosive loads. Current methods in relevant design codes are not specific for preventing progressive collapse of CFST structures. Therefore, it is necessary to carry out numerical simulations on CFST structure under impact loads. Introduction The steel reinforced concrete composite structure as a new structure type with good bearing refractory performance steel reinforced concrete composite structure as a new structure type with good bearing refractory performance, good plasticity and toughness, good seismic performance, and advanced economic index and so on. In the previous design specifications, mainly under the normal load of the safety design, does not take into account the role of accidental load. In recent years, natural disasters, terrorist attacks around the world, since 1960s, there have been three successive structural collapses: 1968 Ronan Point apartment gas explosion [1]; 1995 Murrah federal government building car bomb attacks [2]; 2001 New York world trade building aircraft crash [3]. From these painful lessons we clearly understand the urgency and importance of progressive collapse analysis and design. The definition of continuous collapse means that the structure is destroyed by local damage under the action of unconventional load (such as strong earthquake, impact, explosion, fire, etc.), then the internal force redistribution of the structure causes the other parts to destroy and then form a chain reaction , eventually leading to partial or complete collapse of the structure. It is very difficult to obtain a large number of structural dynamic response test data under the condition of vehicle impact because of the limitation of the dynamic test method. And the finite element analysis method is used to overcome the shortcomings of the structural dynamic test. This paper discussed the analysis method of progressive collapse of CFST column-steel beam with a commercial finite element model (FEM) code ABAQUS.