10.Study on the reinforcement effect and applicability of steel supportunder construction disturbance of overlapping shield tunnels
Author: YANG Zhiwen 1，2 ，LI Wenbo 2，3 ，ZHANG Xu 1，2 ，XYU Youjun 1，2
Abstract:
To explore the reinforcing effect of steel supports on existing tunnels during the construction of overlapping shield tunnels，the study uses the overlapping shield tunnel project from Qinghe Xiaoyingqiao Station to Qinghe Station in the Beijing Metro as a re-search background． By combining monitoring data analysis and numerical simulation methods，the study investigates the impact of newtunnel construction on existing tunnels and analyzes the deformation control ability of steel supports on existing tunnels，as well as theirown stress state． The results show that the construction of the new tunnel above the existing tunnel induces upward deformation in theexisting tunnel． However，the steel supports play a significant role in reducing the uplift and convergence deformation of the existingtunnel． Specifically，the control effect on uplift deformation is 23． 60% and the control effect on convergence deformation exceeds80． 00% ． The stress on the steel supports is primarily concentrated at the vertical braces，long horizontal braces and ring braces，whilethe stress on the short horizontal braces and longitudinal braces is relatively small． The applicability study indicates that steel supportsperform best under construction conditions where the new tunnel has a small clearance and passes over the existing tunnel，providing asolid basis for future applications of steel supports．
Keywords: overlapping tunnel; construction disturbance; steel support; reinforcement effect
Full Text Link: https://link.cnki.net/doi/10.16559/j.cnki.2095-2295.2025.03.010