Abstract In order to analyze the partitioning method and load-bearing characteristics of the prefabricated secondary lining in the composite lining of conventional tunnelling, the "contact friction-beam-joint" composite lining calculation model that takes account of the interaction between linings has been created by using the load-structure model analysis method. With consideration of the normal and tangential constraints on the initial support imposed by the surrounding rock, the contact pressure between the initial support and secondary lining in the composite lining of conventional tunnelling and the internal force of secondary lining have been analyzed. The 6 partitioning methods for prefabricated secondary lining, and the effects of the position of prefabricated block joints and the flexural rigidity of joints on the internal force of secondary lining are also investigated here. As the study results indicate: contact rigidity has major impact on the inter-layer contact pressure, and the maximum contact pressure always occurs at the arch springing of tunnel lining, so it is recommended that the contact rigidity coefficient is selected within the stable range of the contact pressure. The position of prefabricated block joints of secondary lining has major impact on the bending moment of secondary lining but minor impact on its axial force. If the flexural rigidity of joints is in the range of 0~100 MN·m·rad-1, the joints impose the greatest impact on the contact pressure, internal force and deformation of the lining, so it is recommended that the flexural rigidity value of the joints of prefabricated secondary lining is kept in the range of 50~400 MN·m·rad-1.
Abstract：
In order to analyze the partitioning method and load-bearing characteristics of the prefabricated secondary lining in the composite lining of conventional tunnelling, the "contact friction-beam-joint" composite lining calculation model that takes account of the interaction between linings has been created by using the load-structure model analysis method. With consideration of the normal and tangential constraints on the initial support imposed by the surrounding rock, the contact pressure between the initial support and secondary lining in the composite lining of conventional tunnelling and the internal force of secondary lining have been analyzed. The 6 partitioning methods for prefabricated secondary lining, and the effects of the position of prefabricated block joints and the flexural rigidity of joints on the internal force of secondary lining are also investigated here. As the study results indicate: contact rigidity has major impact on the inter-layer contact pressure, and the maximum contact pressure always occurs at the arch springing of tunnel lining, so it is recommended that the contact rigidity coefficient is selected within the stable range of the contact pressure. The position of prefabricated block joints of secondary lining has major impact on the bending moment of secondary lining but minor impact on its axial force. If the flexural rigidity of joints is in the range of 0~100 MN·m·rad-1, the joints impose the greatest impact on the contact pressure, internal force and deformation of the lining, so it is recommended that the flexural rigidity value of the joints of prefabricated secondary lining is kept in the range of 50~400 MN·m·rad-1.
ZHANG Yujin ZHOU Xiaojun YU Bingxin LI Xu ZHANG Chao
.Study on the Partitioning Method for Prefabricated Secondary Lining in Conventional Tunnelling Based on the "Contact Friction-Beam-Joint" Model[J] MODERN TUNNELLING TECHNOLOGY, 2024,V61(3): 35-44
2024, Vol. 61 