Numerical Analysis Of The Influence Of Cast-in-place RC Slab On The Progressive Collapse Resistance Of Frame

In recent years,the progressive collapse of structures has attracted great attention from experts and scholars.In the practical progressive collapse analysis of structures,the role of floor is often ignored in order to simplify the model,and only a simple pure frame model is established.As the main vertical stressed member,floor can enhance the overall performance of the structure,and has a positive impact on the structure’s resistance to progressive collapse.The numerical model without considering the effect of floor cannot well simulate the progressive collapse process of the whole structure caused by local failure.In this paper,based on ABAQUS numerical simulation,the influence of cast-in-place floor slab on the progressive collapse resistance of RC frame structure is studied,and the participation degree of steel reinforcement in the progressive collapse process of floor slab is analyzed in depth,and relevant results are obtained.1.Based on the progressive collapse test of RC frame with 2 floors and 2 spans conducted by the research group,ABAQUS program was used to establish a numerical model to verify the correctness of the numerical analysis,and the influence of horizontal constraint on the collapse resistance of RC frame was analyzed.It was believed that the lateral constraint would improve the collapse resistance of the structure.2.Establish a framework with floor RC frame and pure numerical model,respectively to dismantle the underlying column,Angle,internal column in the long side,and simulate the process of progressive collapsed,contrast analysis of the structure with and without floor stress distribution,force majeure,the key component horizontal displacement and internal force,floor structure collapse resistance increase scope in 20% ~ 57.76%.3.In the floor reinforcement,the closer the reinforcement tension is to the failure column,the greater it will be,and the earlier it will enter the hardening stage.The tensile film effect of the floor is more sufficient.4.The pure frame model with different flange widths was established,and the analysis showed that as the flange width increased,the structure resistance increased and thedeformation decreased,and the effective flange could well simulate the influence of floor slab on the overall structure.The flange width was suggested to be b+2h.