As the most important performance,compliance of shield tunneling machines(STM) is defined as the capability to accommodate the sudden change of the load induced by the variable geological conditions during excavation....As the most important performance,compliance of shield tunneling machines(STM) is defined as the capability to accommodate the sudden change of the load induced by the variable geological conditions during excavation.Owing to the different requirements of the compliant tasks,the existing methods in the robotic field cannot be utilized in the analysis and design of the mechanical system of shield tunneling machines.In this paper,based on the stiffness of the mechanical system and the equivalent contact stiffness of the tunnel face,the tunneling interface-matching index(IMI) is proposed to evaluate the compliance of the machine.The IMI is defined as a metric to describe the coincidence of the stiffness curves of the mechanical system and the tunnel face.Moreover,a tunneling case is investigated in the paper as an example to expound the validation of IMI and the analytical process.In conclusion,the IMI presented here can be served as an appraisement of the capability in conforming to the load fluctuation,and give instructions for the design of the thrust system of shield tunneling machines.展开更多
In large-diameter shield tunnels,applying the double-layer lining structure can improve the load-bearing properties and maintain the stability of segmental lining.The secondary lining thickness is a key parameter in t...In large-diameter shield tunnels,applying the double-layer lining structure can improve the load-bearing properties and maintain the stability of segmental lining.The secondary lining thickness is a key parameter in the design of a double lining structure,which is worth being explored.Based on an actual large-diameter shield tunnel,loading model tests are carried out to investigate the effect of the secondary lining thickness on the mechanical behaviours of the double lining structure.The test results show that within the range of secondary lining thicknesses discussed,the load-bearing limit of the double-layer lining increases with growing secondary lining thickness.As a passive support,the secondary lining acts as an auxiliary load-bearing structure by contacting the segment.And changes in secondary lining thickness have a significant effect on the contact state between the segment and secondary lining,with both the contact pressure level and the contact area between the two varying.For double-layer lining structures in large-diameter shield tunnels,it is proposed that the stiffness of the secondary lining needs to be matched to the stiffness of the segment,as this allows them to have a coordinated deformation and a good joint load-bearing effect.展开更多
基金supported by the National Basic Research Program of China ("973" Program) (Grant No. 2007CB714003)the National Natural Science Foundation of China (Grant Nos. 51075259 and 50905108)the Program for New Century Excellent Talents in University (Grant No.NCET-10-0579)
文摘As the most important performance,compliance of shield tunneling machines(STM) is defined as the capability to accommodate the sudden change of the load induced by the variable geological conditions during excavation.Owing to the different requirements of the compliant tasks,the existing methods in the robotic field cannot be utilized in the analysis and design of the mechanical system of shield tunneling machines.In this paper,based on the stiffness of the mechanical system and the equivalent contact stiffness of the tunnel face,the tunneling interface-matching index(IMI) is proposed to evaluate the compliance of the machine.The IMI is defined as a metric to describe the coincidence of the stiffness curves of the mechanical system and the tunnel face.Moreover,a tunneling case is investigated in the paper as an example to expound the validation of IMI and the analytical process.In conclusion,the IMI presented here can be served as an appraisement of the capability in conforming to the load fluctuation,and give instructions for the design of the thrust system of shield tunneling machines.
基金supported by the National Natural Science Foundation of China(Grant Nos.52178398,51991394,and 51278424).
文摘In large-diameter shield tunnels,applying the double-layer lining structure can improve the load-bearing properties and maintain the stability of segmental lining.The secondary lining thickness is a key parameter in the design of a double lining structure,which is worth being explored.Based on an actual large-diameter shield tunnel,loading model tests are carried out to investigate the effect of the secondary lining thickness on the mechanical behaviours of the double lining structure.The test results show that within the range of secondary lining thicknesses discussed,the load-bearing limit of the double-layer lining increases with growing secondary lining thickness.As a passive support,the secondary lining acts as an auxiliary load-bearing structure by contacting the segment.And changes in secondary lining thickness have a significant effect on the contact state between the segment and secondary lining,with both the contact pressure level and the contact area between the two varying.For double-layer lining structures in large-diameter shield tunnels,it is proposed that the stiffness of the secondary lining needs to be matched to the stiffness of the segment,as this allows them to have a coordinated deformation and a good joint load-bearing effect.
