Abstract：
Among newly built railway tunnels, the composite lining structure adopted in NATM is very popular. The secondary lining is considered to be the auxiliary one if the surrounding rock is highly stable. A tunnel in very soft and fractured rock must have a secondary lining in time to bear part of the load since the primary support will suffer from large deformation and is difficult to stabilize quickly. Additionally, employing a secondary lining too early or late negatively affects tunnel safety. Using the deformation characteristics and analysis of a tunnel with high ground stress on the Lanzhou-Chongqing railway as an example, this paper summarizes the appropriate construction timing of a secondary lining for a tunnel with large deformation in soft rock with high ground stress. Finally the safety of the secondary lining was simulated.
.On the Construction Time of a Secondary Lining for a Tunnel with Large Deformation in Soft Rock with High Ground Stress[J] MODERN TUNNELLING TECHNOLOGY, 2013,V50(2): 84-93
2013, Vol. 50 