The Collapse Behavior Analysis Of RC Frame Structure With The Critical Column Loss On The Ground Floor

Recently, with more natural disasters and emergencies happening, the progressivecollapse of structures is common occurrence. The buildings collapse will result in serious lossof life and massive property damage which draw the attention engineering personnel.Scholars both at home and abroad have done a lot of research on seismic collapse andcontinuous collapse, as two separate areas. The columns at the ground floor usually failduring the earthquake and emergencies, while structural components are usually removed tosatisfy architectural style, which destroys the power transmission path of the structure andlead structure collapse under earthquake. Combined with the earthquake collapse research andprogressive collapse research and based on the alternate path method, the finite elementanalysis software ANSYS/LS-DYNA is used to simulate the whole collapse process ofreinforced concrete frame structure under earthquake with the critical column loss at theground. The influence of the height of the layer, the size of the span, the number of the layerof the frame and the location the column on the collapse resistance performance is mainlydiscussed in the paper.The plane framework simulation models are established, through the comparativeanalysis of collapse resistance performance, it is found that the beam-column joint damagedand then the ground floor quickly transformed into weak layer. The height of the layer, thesize of the span and the number of the layer of reinforced concrete frame structure have greatinfluence on the collapse performance, the analysis shows that it is beneficial way ofearthquake resistance to appropriately increase levels, reduce the span and increase thenumber of story after failure of key column at the ground floor. Conversely, the structure willbecome weak layer easier and collapse.Based on the plane framework simulation models, the three dimensional frameworksimulation models are also established, through the comparative analysis of collapseresistance performance after removing columns at different location, it is found that the framewith the corner column removed is damaged most seriously. And the destructive process of structures can be divided into three stages:(1) elastic deformation stage, and (2) the plasticdeformation stage that the gravitational influence is dominant, and (3) the plastic deformationstage that the seismic effect is dominant.