Research on the technical scheme of pile foundation of bridge under Tuanjiu Phase II tunnel by shield tunneling

Abstract

With the rapid development of municipal infrastructure construction, crossing between new tunnels and existing projects is becoming more common. The shield tunneling method will inevitably cause some disturbance to the surrounding strata, which leads to the instability of the line and threatens its normal operation. In order to explore the influence of shield method on bridge pile foundation, and put forward some solutions with reference significance. Based on the Hongshankou Bridge project of the second phase of Tuan Ninth-phase water transmission tunnel under the Beijing Fifth Ring Road in a short distance, after evaluating the deformation control technical indicators that Hongshankou bridge should meet, the design scheme of lateral tunnel bridge piles is proposed, and the three-dimensional whole process construction simulation is carried out by Midas/GTS to determine whether the bridge structure meets the technical indicators. The result show that the influence of construction on the stability of Hongshankou bridge pile foundation can be reduced by adopting the design scheme of grouting with mud effect, deep hole grouting in the tunnel and strengthening the water sealing capacity of the second lining. By comparing the deformation value of Hongshankou Bridge in the construction process with the control technical index obtained by Midas/GTS simulation, the result show that the structural safety of Hongshankou bridge will not be affected under normal construction conditions of TuanninII water transmission tunnel. The research result can provide reference for the construction design of similar projects.

Keywords

Tuanjiu Phase Ⅱ / shield machine / underpass bridge pile foundation / Midas/GTS finite element