Stability of Temporary Railway Trestle Crossing Deep Excavation

摘要

Ningbo high speed rail station located in the Southeast coastal area of china is one of the newestcomprehensive transportation hub that integrates railway station, subway station and other transfertransportation tool. The foundation pit of the project stretches an area of 265m×124m and a depth of24m. Soil in this area has unfavorable characteristics such as compressibility, sensitivity. A series ofprecautionary measures were adopted in design and construction which facilitated theunprecedented in china the non-phased massive excavation and building of the station house bytemporarily adding a trestle spanning over the foundation pit. This creative technique not onlysaved nearly 1/3 of the construction period compared to the traditional way but also the project cost.In this article the impact on deformation, dynamic characteristic and the vehicle-bridge couplingvibration of the temporary trestle from soil upheaval due to unloading during excavation is studied.