Analysis on Mechanism of Longitudinal Grouting Uplift of Existing Metro
Tunnel
(1 College of Civil and Transportation Engineering, Shenzhen University, Shenzhen 518060;2 Key Laboratory of Coastal Urban Resilient Infrastructures (Shenzhen University), Ministry of Education, Shenzhen 518060)
Abstract:
Compaction grouting uplift is an effective measure to reduce excessive settlement and uneven settlement
of tunnels. Based on the cylindrical cavity expansion theory and the image method, the additional uplift force on the existing tunnel caused by compaction grouting is analyzed and the analytical solution of uplift force considering tunnel displacement influence is derived. Then the existing tunnel is assumed as a Timoshenko beam resting on a Vlasov foundation. Considering the shear dislocation between lining rings and the continuity of foundation, a grouting uplift calculation model on existing metro tunnel is established, and a theoretical solution of longitudinal response of tunnel is given. This method is verified through specific cases, the mechanism of tunnel grouting uplift is revealed,and the effect of key factors on grouting uplift is analyzed. The results show that the grouting uplift effect is sensitive to the change of soil elastic modulus at the bottom of the tunnel, and the influence of the variation on the uplift effect
increases with the decrease of the elastic modulus; the grouting order plays a key role in the effect of tunnel grouting uplift.
FU Yanbin1,
2 CHEN Xiangsheng1,
2 WU Peilin1 etc
.Analysis on Mechanism of Longitudinal Grouting Uplift of Existing Metro
Tunnel[J] MODERN TUNNELLING TECHNOLOGY, 2020,V57(5): 184-192