Abstract
Some mountain tunnels suffer from floor heave after completion, and some of them require countermeasures. This phenomenon occurs if there are no big deformation during construction, therefore, under existing circumstances, based on preliminary survey and condition of excavation, to predict the floor heave deformation after completion is difficult.
In this study, to help the improvement of the prediction accuracy, first, construction data of Shinkansen tunnels suffered from floor heave were analyzed, so that the concernment between deterioration of ground by water and floor heave was confirmed. Second, make the model ground using the rock of actual tunnel, and recreate the floor heave by adding the water to model ground. Finally, tunnel excavation and floor heave after construction are consistently modeled in the numerical analysis. As the result, the effect of early closure and invert shape for floor heave were confirmed.
