超长浅埋大跨河东机场高铁站结构设计研究

Research on the Structural Design of High-speed Railway Station of Hedong Airport with Super-long Shallow-buried and Long Span

研究目的:为分析寒冷地区结构受温度变化的影响,研究地下站跨度大、开洞多且位于设防烈度8度区的结构抗震性能,解决西北地区屋面钢结构在风荷载作用下的连接等问题,本文以银西高铁与银川河东机场航站楼相结合的空铁交通枢纽——河东机场站为例,对该站温度、抗震及钢结构构造等方面进行系统研究。研究结论:(1)气温变化引起地下站房结构的温度应力从车站两端向中部集中,车站中部部位出现应力最大值;(2)温度应力在梁柱节点、板墙相交以及结构开孔处出现应力集中,需采取必要的构造措施和施工措施以减小裂缝;(3)地下站房在中震作用下,结构最大层间位移角均小于1/550,结构处于弹性工作阶段,抗震工况不起控制作用;在大震作用下,弹塑性层间位移未超过1/250的弹塑性层间位移角限值,结构局部处于弹塑性工作阶段;(4)本工程采用的倒三角钢桁架结构稳定性强,适用于大跨屋架结构;轴向对称球形节点,能够有效地抵抗外荷载,提高钢架的整体稳定性;(5)本站的成功实施,为地下超长复杂大跨结构积累了经验,对后期铁路枢纽站房的建设及类似工程具有参考价值和指导意义。

Research purposes:In order to analyze the influence of temperature change on the structure in cold area,study the seismic performance of the underground station with large span,many openings and located in the 8 degree fortification intensity area,and solve the problems of the connection of the roof steel structure in the northwest area under the wind load,this paper takes Hedong Airport Station as an example,which is a transportation hub of Yinxi high speed railway and the terminal of Yinchuan Hedong airport,to systematically study the temperature and seismic resistance and steel structure of the station.Research conclusions:(1)Temperature change causes the temperature stress of underground station structure to concentrate from both ends of the station to the middle part,and the maximum stress occurs in the middle part of the station.(2)The stress concentration occurs when the temperature stress is at the beam-column node,the intersection of plate and wall and the structural opening.Necessary structural measures and construction measures should be taken to reduce the crack.(3)Under the action of moderate earthquake,the maximum inter-storey displacement angle of the structure is all less than 1/550,and the structure is in the elastic working stage and has no control effect in the aseismic working condition.Under the action of large earthquake,the elastic-plastic interlayer displacement angle does not exceed 1/250 of the limit of elastic-plastic interlayer displacement,and the structure is partially in the elastic-plastic working stage.(4)The inverted triangle steel truss structure adopted in this project has strong stability and is suitable for long-span roof truss structure;Axial symmetric spherical joints can effectively resist external load and improve the overall stability of the steel frame.(5)The successful implementation of this site has accumulated experience for the underground ultra-long and complex long-span structure,which has reference value and guiding significance for the later construction of railway hub station house and similar projects.