Study On Seismic Performance Of RC Frame-stepped Wall Structures

The reinforced concrete(RC)frame structure is widely distributed in China and has become the preferred structural form for hospitals,schools and other buildings that undertake major social functions.The RC frame structure has some advantages like flexible space arrangement,light weight and clear force transmission path.However,summing up the major earthquakes in China in recent years,we can find that the RC frame structure highlights the failure mode that is inconsistent with the design.The "strong column weak beam" damage required for seismic design does not appear in the structure but a large number of "strong beam weak column" structure are destroyed,and the underlying weak layer collapses.This failure mode has a bad effect on post-earthquake rescue and post-repair.In this paper,the damage mode is improved by adding some stepped walls in the RC frame structure,and the effectiveness and economy of the measure are comprehensively analyzed.The main work contents are as follows:1.Summarize and analyze the passive seismic measures commonly used in RC frame structures,including base isolation,support frame structure system,rocking wall frame structure system and frame structure system with a small number of seismic walls.The damage control mechanism mainly includes two types: one is to concentrate the damage on a certain part(such as the isolated structure),and the other is to distribute the damage evenly in the structure to realize the overall energy dissipation mechanism.2.Based on ABAQUS,Five beam-column-seismic wall substructure models are established,and the model is subjected to low-cycle reciprocating loading.The stiffness,ductility and energy consumption of the structure after the addition of the seismic wall are analyzed.At the same time,the influence of the difference of the position and force of the seismic wall in the structure on the seismic performance of the structure is analyzed.3.To improve the seismic performance of the overall structure by adding a stepped wall.Based on the Yushu Armed Forces Second Team Barracks destroyed by the Yushu earthquake,five overall structural models were established.IDA analysis was carried out on the RC frame-stepped cross-middle wall structure?the RC frame-stepped wing wall structure and pure frame structure.The seismic response of the structure behind different types of stepped walls,and the degree of improvement of the seismic performance of the structure after the addition of the stepped wall.4.According to the results of IDA analysis,combined with the probability-based seismic loss analysis,the economic loss of the structure under various earthquakes is calculated,and compared with the economic input of the stepped wall,the economic rationality of the RC frame-stepped cross-middle wall structure and the RC frame-stepped wing wall structure are calculated.