暗挖地铁车站大跨度拱形中板的设计研究

为实现地铁车站站台层大跨度无柱功能,以青岛地铁1号线薛家岛站拱形中板的设计为背景,运用有限元方法分析研究不同形式中板在静力及地震作用下的结构受力特性。分析结果表明:(1)静力分析中,拱形中板较其他形式中板而言,仅轴力值较大,其余内力及变形值均相对较小;跨中弯矩在外侧水土压力作用下为负弯矩,并呈正比例变化;受空间作用影响,洞口梁及节点处应力集中明显,梁扭转效应明显。(2)抗震分析中,E2、E3作用下得出中板时程位移曲线,最大层间位移角均满足规范限值要求; E2作用下,拱形中板构件内力较非地震工况增幅约25%。

Research on the Design of Large-span Arched Medium Plate in Metro Station

In order to achieve the function of large-span and column-free metro station platform, this paper uses the finite element method to analyze the force characteristics of different medium plates under the action of static force and earthquake with reference to Xuejiadao Station of Qingdao Metro Line. The results are as follows:(1)Compared with other medium plates, the arched medium plate only shows a larger axial force value in the analysis of static force, the mid-span bending moment is negative under the action of the outer water-soil pressure and changes proportionally. Subjected to spatial effect, the stress concentration at the beam and joint of the tunnel and beam torsion effect are is obvious.(2) The time history curves of displacement of the medium plate is obtained by E2 and E3. The maximum interlayer displacement angle meets the specification limit requirements in the analysis of earthquake. The internal force of the arched medium plate is about 25% higher than that of the non-seismic working condition under the action of E2.