西安咸阳国际机场东航站楼隔震设计

Seismic isolation design on east terminal building of Xi’an Xianyang International Airport

西安咸阳国际机场东航站楼主体结构为钢筋混凝土框架结构,屋盖及其支撑体系为钢结构。中央主楼核心区长486m,宽252m,作为人流密集的国家级交通枢纽工程,建筑功能复杂,抗震设防标准高,设计采用了层间隔震技术。隔震层由铅芯橡胶隔震支座、普通橡胶隔震支座、弹性滑板支座和黏滞阻尼器组合而成。隔震相关计算分析及验算结果表明,设防地震作用下隔震后上部结构楼层剪力及楼层加速度降低至非隔震时的38%以下,隔震层上部结构可按降低设防烈度1度进行设计。罕遇地震下隔震层下柱墩变形及承载力验算结果表明,通过设置型钢拉梁层能够使其满足罕遇地震下的变形及承载力要求。隔震结构的温度效应计算结果表明,隔震后结构温度应力效应显著降低,通过合理设置结构后浇带,隔震层在施工阶段及正常使用阶段的温度变形均能满足预期的性能要求。最后采用时程法研究了隔震层在遭遇罕遇地震后的自复位能力,结果显示,隔震层震后残余变形较小,自复位能力良好。

The main structure of the east terminal building of Xi’an Xianyang International Airport is a reinforced concrete frame structure, and the roof and its supporting system are steel structures. The central core area of the main building is 486 m long and 252 m wide. As a national-level transportation hub project with dense crowds, the building functions are complex and the seismic fortification standard is high. Therefore, the design adopts floor-level seismic isolation technology. The vibration isolation layer is composed of lead rubber bearings, linear natural rubber bearings, elastic sliding bearings and viscous dampers. According to the relevant calculation analysis and checking calculation of seismic isolation, the floor shear force and floor acceleration of the superstructure after the seismic isolation were reduced to less than 38% of the non-isolation state, and the superstructure of the seismic isolation layer was designed according to the reduction of the fortification intensity by 1 degree. The deformation and bearing capacity of the column piers under the seismic isolation layer were checked for rare earthquakes, and the steel tie beam layers are set to make them meet the requirements of deformation and bearing capacity under rare earthquakes. The temperature effect of the isolation structure was studied, and the results show that the temperature stress effect of the structure is significantly reduced after isolation. By rationally setting the post-poured belts of the structure, the temperature deformation of the isolation layer during the construction stage and the normal use stage could meet the expected performance requirements. The time-history method was used to study the self-resetting ability of the isolation layer after encountering the rare earthquake. The results show that the residual deformation of the seismic isolation layer after the earthquake is small, and the self-resetting ability of the isolation layer is good.