Study On Seismic Behavior Of Reinforced Concrete Core Walls With Cantilevered Steel Truss Platform Located At A Higer Level

In our country, the steel-concrete mixed structure is widely used in the high-rise building because it holds the merits of both steel structure, such as better earthquake-resistance performance, fast construction speed, and those of concrete structure like big lateral stiffness, low cost etc. Therefore, the steel-concrete mixed structure is more adaptable to the national condition of china. At present, the application of the structure style is wider and wider, and the building in such style is constructed higher and higher with increasing constructional complicacy.In this paper, the seismic behavior of one special steel-concrete mixed structure, the reinforced concrete core walls with cantilevered steel truss platform located at a higher level, is studied. Until now, the research on steel-concrete mixed structure style is rare. To ensure the earthquake-resistance safety and decrease seismic hazard, systematic and profound research on the earthquake-resistance performance and designing method of such structure style is of important application valuable.Basing on such background, the main turret of a real project is analyzed in this paper. According to the algorithm of finite element theory, an appropriate calculation model is established; the dynamic performance, spectrum response, elastic time-history response and elastic-plastic time-history response of the structure is accomplished. At last, the earthquake response characteristic of the buildings in such style is concluded, which can provide reference for the design of practical project.The analysis indicates that the vertical seismic force has greater impact on the cantilevered steel truss platform which shows an obvious vertical whiplash effect, therefore, the three-dimensional seismic effect should be conducted in seismic response analysis. In strong earthquakes, the redundancy of the cantilevered steel truss platform is lower, and it will collapse when the cantilevered roots damage. Basing on the study of hinge order and damage mechanism of steel truss, a program of viscous dampers installation and steel bar truss section optimization is proposed, which greatly enhances the seismic behavior of the cantilevered steel truss platform and guarantees the steel truss "damaged but not failed" in strong earthquakes.