| The masonry-infilled frame structure, which has economic and applicability, ispopular in civil engineering. Infilled walls, as nonstructural components, are often neglectedor just consider its influence on the structural natural vibration period in the structural designand analysis, because of the complexity of frame-infilled interaction. Earthquake disaster hasdemonstrated that infilled walls changed the dynamic characteristics of structure in a largeextent, have a certain influence on the overall seismic performance of the structure.It is known that the main-earthquake and post-earthquake is symbiotic, and there are alarge number of post-earthquake after the large main-earthquake, so post-earthquake play akey role in deepening damages, and even cause the collapse of the buildings. Domestic andaboard researches mainly account of the single response of the earthquake，therefore it is aurgent problems in earthquake engineering to study the damage to what extentpost-earthquakes could deteriorate the damage.In this study, from the reviewing the scholar’s researches on infilled walls andpost-earthquakes, the damage mechanics theory and the IDARC program has been employedand used to analyze the elastic-plastic characteristic of the structure under earthquakes, mainlystudies and findings are listed as below:1. Four kinds of typical RC frame structures, in which infilled-wall vertical arrangementis different, have been invistigated. The influence of infilled walls on structure seismicperformance and damage performance under the three seismic waves,(chosed as EL Centroseismic wave, Taft seismic wave and Shifang seismic wave) in the frequent earthquake,resistance earthquake and rare earthquake has been analyzed。The results indicate that thestiffness of infilled-wall is the main reason for different structural seismic behaviors and can’tbe ignored on seismic design of RC frame structure.One of the four models has been analyzed in detail for establishing structuralperformance prediction model, and it is found that the overall structural damage index DIincreases along with the increase of the peak ground acceleration. The relationship betweeninfilled walls’ damage behavior and storeys, the relationship between infilled wall materialsand the structural deformation have been also investigated, the results show that the damageof infilled-wall from top to bottom gradually increases，and the greater the stiffness of theinfilled-wall material is, the more obvious the abrupt stiffness of the structure is.2. Four two-span RC frame structures, which has different height, have been analyzed. Relationship curves between height of the structure and deformation are obtained, thedeformation curve of masonry-infilled frame structure shows that the compositecharacteristics is shear-bending deformation mode, and the deformation is more obviousalong with the increase of number of storey.3. Two analysis models under18load cases are considered to study the impact ofpost-earthquake on the damaged-structure，the results indicate that the serious damagedstructure is more vulnerable to the post-earthquake, distribution of cracks and plastic hinges inthe beam end is different from that in the intact structure. The main reason is that themain-earthquake has changed stiffness distribution of the damaged structure. Due to thepost-earthquake deteriorating the seismic damage of the structure, so the steel support as themain components for rapid seismic retrofitting of damaged-structure is selected to improvethe seismic capability of the structure, and the study shows that the damage state of the structurebefore and after reinforcement is different. |
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