Environmental Engineering Deformation Control of High-speed Railway Shield Tunnel Under Crossing Bridge Piles

Abstract

With the continuous acceleration of my country’s high-speed rail construction, it is inevitable to cross the existing engineering structure during the construction process. During the construction of high-speed railway, the control of the influence and deformation of the existing structure is a subject that needs to be studied in environmental engineering. Hangzhou metro line 1 is designed to cross under the Hu-Hang high-speed railway. According to the design, the shield tunnel is very close (minimum distance 5.19m) to the bridge piles of the Hu-Hang high-speed railway. Therefore, how to control the deformation of the bridge piles is a big problem in the shield tunnel excavation. Before construction, the method of the bored piles coupled with the jet grouting piles was proposed. The 3D numerical model was built to study the deformation of the bridge piles with the cases of the shield tunnel excavation without soil consolidation, the construction of the bored piles coupled with the jet grouting piles and the shield tunnel excavation with soil consolidation. The results show that the method of the bored piles coupled with the jet grouting piles can control the deformation of the bridge piles in the shield tunnel excavation effectively. Then, the deformation monitoring of the bridge piles was performed in the process of construction. The monitored data were close to the calculated results, which implies that the method of the bored piles coupled with the jet grouting piles is effective.