Seismic Design Of Multistory Reinforced Concrete Frame Structure Based On Integrity

Frame structure is widely used in shopping malls,office buildings,parking lots and other buildings because of its simple form,flexible plane and easy to form large building space.For the middle and high-rise frame structure,the axial force of the bottom column is relatively large.In order to meet the requirements of axial compression ratio,the section size of the bottom column is often large.The external corner of the bottom column protrudes,which affects the indoor beauty and furniture layout.The architectural design usually hopes that the section size of the column in the frame can be appropriately reduced.At present,the seismic design of our country considers the seismic calculation and seismic measures separately,calculates the strength and deformation of the structure under the action of frequent earthquakes,and controls the internal force adjustment and structural seismic measures through the seismic grade,less involves the overall grasp of the seismic performance of the structure.In addition,in order to simplify the calculation and analysis,only one frame is usually considered in the frame structure with regular layout.In fact,the spatial arrangement of the floor,the two-way input of seismic wave and the regularity of the structure have a great influence on the integrity and seismic performance of the structure,so it is necessary to consider the spatial effect of the frame structure.This paper focuses on the design concept of the perimeter strengthening frame,compares the seismic design methods of China and the America and Europe,grasps the relationship between the structural bearing capacity and ductility from the perspective of integrity.In order to introduce the anti-seismic design idea of the perimeter strengthening frame,the model calculation examples of the space frame and the perimeter strengthening frame are designed respectively according to the code of our country,and the anti-seismic performance of the two kinds of frames under the frequent earthquake and the rare earthquake is studied by using the time history analysis method.The main contents are as follows:(1)The architectural requirements of the frame structure and the significance of the conceptual design is briefly stated.Focusing on the design concept of the perimeter strengthening frame,it compares the seismic design methods of China,America and Europe,and summarizes the research status of the perimeter strengthening frame at home and abroad.(2)The element parameters of finite element modeling and the basic theory of time history analysis method are described in detail,and the correctness of SAP2000 software is verified by simulating the seismic test of multi-storey reinforced concrete frame structure.(3)The design idea of the perimeter strengthening frame is introduced,and the corresponding seismic design process is proposed according to the code of our country.Each uniform seismic space frame K1 is designed,the perimeter strengthening frame ZJK1-1 with the section size of only the perimeter frame increased and the perimeter strengthening frame ZJK1-2 with the support are designed.Seven seismic waves,which are statistically equivalent to the 8°(0.20 g)response spectrum of the code,are selected to study the vertex displacement,interlayer displacement angle and plastic hinge of K1,ZJK1-1 and ZJK1-2 under the action of frequent and rare earthquakes by time history analysis.In addition,the reinforcement ratio of the beam and column members of the frame structure is calculated to investigate the economic benefits of the perimeter strengthening frame.(4)The influence of seismic fortification intensity on the seismic performance of the surrounding reinforced frame is studied.On the basis of 7°(0.15 g)seismic fortification intensity,the space frame K2,the perimeter strengthening frame ZJK2-1with the section size of only the perimeter frame increased and the perimeter strengthening frame ZJK2-2 with the support are designed respectively.And the seismic performance of K2,ZJK2-1 and ZJK2-2 under two-way earthquake is studied by time history analysis method.(5)The influence of building layout on the seismic performance of the surrounding reinforced frame is studied.Based on the dynamic characteristics of the rectangular plane structure,the space frame K3,the perimeter strengthening frame ZJK3-1 with the section size of only the perimeter frame increased and the perimeter strengthening frame ZJK3-2 with the support are designed respectively.And the seismic performance of K3,ZJK3-1 and ZJK3-2 under two-way earthquake is studied by time history analysis method.