Abstract Shield launching and arrival are key and risky elements in the construction of shield driving tunnels. To prevent an unstable enclosure structure, the soil mass at the end side of the tunnel must be consolidated. In this paper, the pros and cons of conventional reinforcement methods are analyzed and compared. Consolidation should be selected by considering the following: geological conditions, groundwater level, overburden, shield type and diameter, working environment, construction safety and accessibility, economy and construction period, etc. As for the case of the Tianjin Metro, a combination of the horizontal grouting and freezing methods was adopted and the concrete measures are described.
Abstract：
Shield launching and arrival are key and risky elements in the construction of shield driving tunnels. To prevent an unstable enclosure structure, the soil mass at the end side of the tunnel must be consolidated. In this paper, the pros and cons of conventional reinforcement methods are analyzed and compared. Consolidation should be selected by considering the following: geological conditions, groundwater level, overburden, shield type and diameter, working environment, construction safety and accessibility, economy and construction period, etc. As for the case of the Tianjin Metro, a combination of the horizontal grouting and freezing methods was adopted and the concrete measures are described.
.Application of the Freezing and Horizontal Grouting Methods
to the Shield Arrival for the Tianjin Metro[J] MODERN TUNNELLING TECHNOLOGY, 2013,V50(3): 183-190
2013, Vol. 50 