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

The disturbance created by the construction of a subway station and running section may be eased by en? larging excavation using the shallow bored construction method for a single-tube double-track shield tunnel, thereby 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 Airport 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 proposed. An optimization study on the rational design parameters for the three-arch station structure is carried out.