In a shallow tunnel, tunnel construction will triggers a chain of ground movements, resulting in settlements at the ground surface, which become more significant with the decrease in tunnel depth. Therefore, by considering behaviour of the segment tunnel joints (can affect the integrity of tunnel in both circumference and longitudinal directions), the surface settlement trough were investigated. Initial model of dual segmental tunnel lining was model and validated with laboratory test to gain nonlinear response of segment joint. Then, a soil-tunnel simulation model was developed with various segment joint parametric models for Singapore Circle Line Stage 3 (C852) project. Results showed that with the use of flexible segment joints that allow movement (hinge-nonlinear model) in staggered ring tunnel model, the ground deformation depicted higher resemblance of surface settlement pattern to the field data. Steady state settlement was observed after 10m of cutter head distance.
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