EVALUATION OF JOINTS INFLUENCE ON SEGMENTAL TUNNEL LINING BEHAVIOR

The use of TBM for excavation and construction of tunnels such as subways, roads, and railroads in urban areas are rapidly increasing. Yet, design of segmental tunnel linings are based on empirical methods. These methods ignore the influence of type of segmental joints and variations of stress distributions in cross-sectional areas of the segmental linings, while the behavior of tunnel lining is significantly affected by the segmental joints type and hence, they cannot predict realistic structural behavior of the lining systems. This paper deals with two-dimensional finite element analyses of the segmental tunnel lining for three conditions; segmental lining models without joints; segmental lining models with pin joints; and with real behavior of joints. Numerical modeling includes linear-elastic springs to model the surrounded ground and rotational springs at joint of the segments. The final results of the analyses illustrated that different joint types have little effect on the radial deformation of ring, therefore using extracted moment-rotational behavior of joints causes realistic bending moment distribution, between the hinged and fix cases of segmental joints.

کلیدواژه ها:

mechanized tunnel ، segmental lining ، lining joints ، ring performance ، finite element method