单洞双线盾构隧道扩挖地铁车站方案研究

Design and Construction of a Metro Station by Enlarging a Single-Tube Double-Track Shield Tunnel

在单洞双线盾构隧道基础上通过浅埋暗挖等工法扩挖形成地铁车站可以解决车站段与区间段施工工期的矛盾,避免盾构机拖拉过站,减小车站施工对周围环境的扰动。文章依托北京地铁机场线西延北新桥站工程,开展了盾构隧道扩挖地铁车站方案研究,设计了采用PBA工法扩挖形成两连拱车站和三连拱车站两种方案。采用MIDAS对两种方案进行数值模拟计算,推荐采用三连拱扩挖方案作为最优方案,并对三连拱车站结构合理设计参数进行了优化研究。

The disturbance created by the construction of a subway station and running section may be eased by enlarging excavation using the shallow bored construction method for a single-tube double-track shield tunnel, there- by avoiding having to drag the shield machine through the station and reducing the hassle of station construction on the surrounding environment. Based on the Beixinqiao station of the West Extension Line of the Beijing Subway Air- port Express, double-arch station and triple-arch station schemes using the PBA construction method are designed, a numerical simulation of these schemes is conducted using MIDAS and ultimately the triple-arch scheme is pro- posed. An optimization study on the rational design parameters for the three-arch station structure is carried out.