全框支厚板转换斜交高层结构抗震性能研究

Study on seismic behavior of skew high-rise building with fullframe supported thick slab transfer

设计制作1∶15全框支厚板转换高层结构的微粒混凝土振动台试验模型,进行7度小震、中震、大震以及8度大震作用下单向、双向、三向共计44组工况的振动台试验,研究动力特性、动力放大系数、层间位移角等性能指标,揭示结构塑性损伤发展机制,进一步采用数值模型研究上部塔楼斜交角度对结构抗震性能的影响。结果表明,全框支厚板转换高层结构具有优良的抗震性能,模型结构经历8度大震后,全框支层未见明显裂缝,处于轻微损坏与完好之间,塔楼剪力墙底部和连梁端部裂缝发生明显,薄弱部位集中在3~10层;模型结构动力放大系数沿高度呈“S”形分布模式,在塔楼顶部放大明显,而全框支层的动力放大系数在不同烈度地震作用下始终处于1~2之间;塔楼斜交角度对此类结构体系动力特性和动力响应的影响很小,全框支层均能对上部不同斜交角度的塔楼起到充分的约束作用,上部塔楼承担绝大部分地震输入能量,全框支层的动力放大系数和动力响应均远低于上部塔楼,全框支厚板转换斜交高层结构体系能够实现“强全框支层弱塔楼”设计理念。

The 1∶15 scaled full-frame supported high-rise building with skew design between upper tower and lower part for shaking table test was designed and manufactured.A total of 44 test cases with 7-degree small earthquake,moderate earthquake,large earthquake&8-degree large earthquake and with one-way,two-way&three-way earthquake inputs were carried out.Some performance indexes,including dynamic characteristics,dynamic amplification coefficient,drift ratio,were studied to reveal the plastic damage mechanism of this structural system.Furthermore,the influence of the skew angle of the upper tower on the seismic performance of the structure is studied based on numerical simulation.The results show that the high-rise structure with full-frame supported thick plate transfer has excellent seismic performance.After experiencing the 8-degree earthquake,there is no obvious crack and damage in the full-frame supported floor,which corresponds to a state between slightly damaged and intact.The cracks at the bottom of the tower shear wall and those at the end of the coupling beam are obvious,and the weak parts are concentrated in the 3~10 floors.The dynamic amplification coefficient of structure is distributed in a“S”shape along the height,and its magnitude is large at the top of the tower,while the value of the dynamic amplification coefficient of the full-frame support layer is always in the range of 1~2.The tower skew angle has little influence on the dynamic characteristics and dynamic response of this kind of structural system.The full-frame supported layer can fully restrain the upper tower with different skew angles.The upper tower undertakes most of the earthquake input energy.The dynamic amplification coefficient and dynamic response of the full-frame supported layer are far lower than those of the upper tower.The design concept of“strong full-frame supported layer and weak upper tower”can be well implemented by the skew tall structural system with full-frame supported thick slab transfer.