Analysis Of Influence Of Stairs On Frame Structure Under The Action Of Earthquake

Frame structure is a structure system which is widely used in the current building structure. At present,model are usually not input staircase components in seismic design, which used to do calculating and analysing, only the staircase in the openings, and the peripheral components of vertical load applied to the stairs. But through research and investigation after the earthquake damage to the stairwell,we found no serious damage in the main structure of many frame structure but the structure was severely damaged, and many stairs are prior to the main structure damage. It as evacuation of escape,and acts as the role, but it did not come out to play in the natural disaster before, unable to protect the lives and property safety, therefore, in the structure design, we should also take into account the staircase on the frame structure of the role and impact.Because of the existence of the stairs, the local stiffness of the frame structure,,the stairs will absorb the earthquake force certain under the action of earthquake.Without considering the stairs model and considering the stairs model are compared with each other under the action of earthquake, in the framework of beams and columns of the stress difference, it is necessary to analyze and contrast. This paper designed two frame structure model in accordance with the specification of concrete and seismic specification, model1does not consider the staircase effect, model2consider the effect on the frame structure of the staircase, and by the analysis and comparison of the two models of the SAP2000V14finite element analysis software, it is obtained by considering the staircase of frame the structure, it is very necessary.The main work of this thesis includes:1. On the basis of theoretical analysis, this paper established two models by SAP2000V14analysis softwar,which considering stairs and without considering stairs, the two different models were analyzed and compared, we study on the stairs would have any effect on the frame structure;2. Through modal analysis was conducted on two model, it have the natural vibration period and the participating mass ratio with two model, After the comparison of them, we get graphic design which is reasonable, and the stairs improves the frame structure of the torsional stiffness;3. Through the analysis of the two models of response spectrum, when considering the stairs, in the earthquake and is not affected by the earthquake, change, internal forces of each member of the structure are the base shear force, displacement and inter-story displacement angle;4. Based on the above analysis and comparison, some suggestions on the staircase design put forward.