| In Japan, some mountain tunnels are damaged by earthquakes and relative large-scale
deformations such as the collapse of permanent lining and the deformation of supports have occurred.
Though earthquake resistant countermeasures for tunnels has been examined recently, some countermeasures for existing tunnels are performed based on the result of tunnel inspection rather than the need against earthquake resistance. To clarify the effects and the mechanical behavior of countermeasures, the model experiment was conducted assuming actual road tunnels. The collapse mechanism was compared among the cases when various kinds of reinforcement to the tunnels were performed, such as rockbolts, fiber sheet, rebar. Results showed that the improvement of load-bearing capacity of the lining was limited, however the prevention of falling concrete blocks from structure could be expected. |
