| 摘要 |
PROBLEM TO BE SOLVED: To provide a shield for an approach-cum-road tunnel, and a method of constructing a section from an approach tunnel to a road tunnel of a main lane. SOLUTION: The shield for the approach-cum-road tunnel functions to convert a horizontally long approach shield into a road tunnel shield of a circular shape, a horseshoe shape, or an inverted horseshoe shape. The approach shield is formed of: a left portion left inside the approach tunnel; a removed portion forming an upper or a lower portion of the same and to be removed; and a converted portion to be converted into the road tunnel shield. Then a newly produced potion of the road tunnel shield is combined with the convertible portion, and thus the approach shield is converted into the road tunnel shield. When the tunnel is constructed the horizontally long approach shield is started from a shield starting shaft to form the approach tunnel, and part of the approach shield is converted into the road tunnel shield in a shield converting shaft or in a shield converting underground space, to thereby construct the road tunnel by the road tunnel shield. COPYRIGHT: (C)2009,JPO&INPIT |
