3D modelling of concrete tunnel segmental joints and the development of a new bolt-spring model

In a segmental metro tunnel, it is widely observed that cracks, water leakage and other structural defects usually appear at joint section of smaller stiffness than main tunnel segment section. this study, 3D finite element analysis was conducted to simulate typical concrete explicitly using continuum elements, the performance model validated against laboratory tests available in literature. Since such may cost excessive computational time when large-scale structure analysed, new bolt-spring developed simplify features joint. model, interaction between bolt modelled by set normal springs shear springs: mainly determined itself, whilst take account bolt-segment friction, resistance bolt. meanwhile, two adjoining segments contact elements. The proposed able details deformation pressure more realistically previously conventional methods (e.g. continuous ring, beam-spring (BSM)), where segment-segment not explicated modelled. Compared saves up 90% without compromising numerical accuracy. Furthermore, paper compared mechanical behaviour cast-iron one with particular emphasis on development different models.