| Reinforced concrete frame structure(RC frame)is widely used in schools,hospitals and other buildings that play an important role in society.In recent years,in the devastating earthquakes in China,a large number of RC frame structures have been damaged and collapsed,and the damage pattern is not consistent with the design expectation,resulting in serious casualties and economic losses.It is manifested that the frame column is severely stressed and it is difficult to achieve the "strong column weak beam" damage mode,and there are problems such as single seismic line and difficult repair.According to statistics,the collapse rate of the frame structure in the Wenchuan Earthquake extreme earthquake zone is as high as 63%,but the Beichuan Salt Bureau staff dormitory in the extreme earthquake zone has not collapsed due to the addition of appropriate wing walls to the bottom frame columns,and the damage is mainly concentrated in the wing walls and beams.The added wing wall has sufficient energy consumption and uniform destruction,and does not form a weak member or a weak layer which can cause failure of the structural load bearing,and exhibits excellent seismic performance.The design of the additional wing wall is flexible,without changing the appearance and function of the structure,low cost and convenient construction.This paper studies the seismic collapse resistance and seismic economic loss of the composite structure system from the substructure composed of beam-column wing wall to the whole structure hierarchy as follows:(1)The RC frame structure strengthened by the wing wall is compared with the special-shaped column structure,the frame shear wall structure and the supporting structure.Summarize the similarities and differences between the RC frame-wing wall structure and other structural systems and the status of wing wall at home and abroad.(2)According to the frame size of the bottom frame of the dormitory building of Beichuan County Salt Service Bureau in Wenchuan Earthquake,three two-span single-story and one-story frames were designed with a scale ratio of 1:3,which are pure frame model,the wing wall that is not affected by axial force(functional separation type)and the wing wall that is affected by axial force(functional integration type).They were subjected to pseudo-static test to study the effects of two wing wall reinforcement modes on the seismic performance of the frame structure.Modeling analysis was performed by ABAQUS finite element software.(3)In order to study the influence of the wing wall reinforcement system on the seismic performance of the whole structure,seven frame structures(one pure frame structure and six wing wall reinforcement frame structures)were redesigned based on the ground floor of the staff dormitory building of Beichuan Salt Bureau.The structural model is analyzed,and the IDA analysis is carried out on the structure of the seven examples.By analyzing the probability that each structure reaches each limit state under different ground motion intensities and comparing the CMR coefficients of different structures,the anti-collapse ability after the wing wall is added,and determine the key parameters of the RC frame-wing wall design for the wing wall design.(4)Using PACT software combined with ABAQUS model to perform performance-ba sed seismic analysis of the example structure,analyze the post-earthquake repair cost,repair time,number of casualties,etc.,so as to optimize the investment-revenue rationality of the wing wall structure,and ensure the structure.It does not collapse and increases the economic rationality of the structure under strong earthquakes. |
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