The Progressive Collapse Analysis Of The Composite Frame With Diaphragm Plate Connections

Concrete-filled steel tubular structure as a new type of structure, due to its unique performance advantages that has been widely used in the actual project. In this paper, ABAQUS finite element analysis software for concrete filled steel tubular connections and frame structure resisting progressive collapse performance in-depth study, the main job of the following aspects:(1) The establishment of a concrete column-H beam with diaphragm plate connections, use the form Pushdown loaded on top of the column node displacement load bearing capacity in order to obtain the curve at the bottom of the column after failure in the diaphragm plate connections destruction morphology, and resistance mechanisms curve, while the impact on the basis of a combination of resisting collapse nodes Capacity 8 key parameters analyzed, including parameters such as material strength steel beam, steel strength, concrete strength, the inner strength of the separator and dimension parameters such as column steel ratio, within the thickness of the separator, the separator within the steel beam width and height;(2) Based on the above analysis of the ring plate node, multi-scale modeling method to establish a 6-bay floor concrete filled steel tubular frame structure, failure of columns at the node using solid modeling unit and housing units, while the remaining frame structure Research methods beam element modeling, and nonlinear dynamic analysis of dismantling after its bottom side columns and column resisting progressive collapse of the remaining structure. Analysis, a time to remove the bottom of a column member, in order to analyze the current dismantling key pillar of the overall structure of the impact of resisting progressive collapse;(3) Also uses the same modeling framework for the establishment of a flat 6-storey steel concrete space frame structure, according to GSA 2003[7] be split column analysis, the key column for the removal of the long sides of the bottom of the column, the short side of the column, interior column and corner posts were extracted key column after column unit was dismantled failed node displacement-time curve, beam-column nodes surrounding the axial force variation and moment to analyze the situation changes after the key underlying column has been removed the remaining structure to resist progressive collapse of the response;(4) Since floor space frame structure during normal force will form a film effect, and therefore should be calculated and analyzed in the framework of spatial analysis of the floor force method. When concrete filled steel tubular space frame structure for modeling, layered shell element method simulation modeling of reinforced concrete slabs in the actual structure of the stress state, extract key column before and after removal of the plastic strain vector nodes surrounding floor, floor analysis force and deformation.