Abstract:
Aiming at the structure deformation and ground surface settlement caused by construction of a new tun? nel approaching existing tunnel, the comprehensive control measures like grouting reinforcement of soil mass of the existing metro line, pre-supporting of newly bored running tunnel, strict control of construction technology, monitoring and early warning were proposed based on the bored running tunnel of Chengdu metro line 8 passing beneath existing shield-driven running tunnel of Chengdu metro line 7. The key points of dewatering and drainage, pipe-roofing and ductile grouting were described. The research shows that the monitoring data present a strong correlation with the construction process, the maximum ground surface settlement is up to 9-10 mm, while the maximum ground surface settlement of monitoring section with the comprehensive control measures is less than 7 mm, and the maximum settlement of the existing metro tunnel structure is less than 6 mm, meeting the requirements of design and specification.
LI Junjie
.Influence on Deformation and Control Measures: A Case Study of Bored Running Tunnel Construction Adjacent to Existing Subway Tunnels[J] MODERN TUNNELLING TECHNOLOGY, 2019,V56(4): 168-174