Influence of shield driving speed on ground surface#br#
settlement in clay layers
Qin Ruicheng1,2 Li Xinggao1,2
1. School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China;
2. Key Laboratory of Urban Underground Engineering of the Ministry of Education, Beijing Jiaotong University, Beijing 100044, China
Abstract:Shield tunneling speed is an important part of shield construction control, but there are few studies on the relationship between shield tunneling speed and surface settlement. This paper analyzes the construction of shield tunneling under the Changzhou clay layer under the background of Changzhou Metro Line 2 shield tunnel construction and characteristics of the influence of speed on surface settlement. Through collating and analyzing the surface monitoring data and combining with the shield tunneling construction log, a numerical simulation method that can quantitatively analyze synchronous grouting, secondary grouting, earth cabin pressure, shield tunneling speed, etc.is proposed to design the simulation Under the working conditions, the whole process of shield tunneling was simulated and researched, and the correspondence between calculation steps and shield tunneling speed was obtained, and the ground subsidence prediction curve caused by the tunneling speed of shield tunneling in the clay layer in Changzhou was established. The research results show that the surface settlement caused by the faster driving speed is smaller, and when the driving speed is 20~50 mm/min, the prediction curve of the relationship between the driving speed and the surface settlement in the clay layer is obtained by numerical simulation: h=6.5/{1+86.2[(v-19.5)/27842.7]0.464}, the prediction effect is good.