BRIDGE SUPERSTRUCTURE

PROBLEM TO BE SOLVED: To construct a box girder by using a precast concrete board as a web in bridge superstructure works. SOLUTION: In a bridge superstructure in which the web is installed between a lower floor slab and an upper floor slab and the box girder is constituted, the web is composed of a prestressed concrete board in which a PC steel material is tensioned in the vertical direction, and extremely-stiff strength concrete having 28-day compressive strength in 100 to 180 N/mm2is used as the concrete of the prestressed concrete board. Extremely-stiff strength concrete having the self-contraction quantity of 400 μm or less per 1 m in an age of 60 days is used. The PC concrete board is manufactured in a factory or on a site-fabrication yard, the concrete board is carried at a building place and installed at a place correspoding to the web of the box girder and the box girder is constructed by cast-in-placing the lower floor slab and the upper floor slab. COPYRIGHT: (C)2004,JPO