Ryosuke Oka

Study on design method of tunnel lining considering initial ground displacement

Mitsutaka Sugimoto

Analysis model for tunnel lining design can be classified to continuum model and beam-spring model. Recently, a beam-spring model, which can consider the active earth pressure due to the excavation surface movement toward tunnel inside, the ground displacement before excavation, and the self-stabilization of ground, has been developed. This model can represent rationally the earth pressure acting on lining, and the displacement and sectional force of lining. However, this model can not take account of the influence of tunnel face advance and calculate the ground surface settlement.
To overcome the above-mentioned problems, this research aims to develop a continuum model, in which ground is modeled by 2-D strain elements, extending the above beam-spring model. The lining displacement and the earth pressure acting on lining were analyzed by the newly developed model. Moreover, the obtained results were compared with those by the existing beam-spring model. As a result, it was found that the both analysis models provide the same tendency of the earth pressure acting on lining and the lining deformation mode. Therefore, the validity of the interaction model between ground and lining in this continuum model could be confirmed. As a future research, it is recommended to consider initial stress analysis, carry out parameter studies, and apply this model to site data.

Please use "previous botton" to return the previous page