Bridge on the Road I/35 Across Václavický Fishpond

The paper describes the design and construction of a bridge across a pond and a local road on the road I/35 Bilý Kostel - Hradek nad Nisou. The bridge comprises 5 spans with lenghts of 40,00 + 3 x 50,00 + 40,00 m. Total length of the bridge is 247 m. The substructure of the bridge consists of concrete abutments and four intermediate concrete piers. Abutment foundations are supported on bored piles and intermediate pillars on spread foundations. Two pillar foundations have been constructed on the lake bed which required sheet pile cofferdam. The superstructure was manufactured by sections in a dedicated area and launched using the incremental launching method. The continuous steel-concrete composite superstructure was designed as a twin steel plate girder with steel bracings and a top flange connected to a composite concrete haunch slab. Plate girders both of which rest upon a set of pot bearings are 2,5 m high and 7,0 m apart. The fabrication yard was stationary and located behind the abutment. A lightweight nose was fitted to the cantilever end of the superstructure to reduce the cantilever deformations during launching. The bridge supports were equipped with special teflon sliding bearings and friction was recorded at each jacking operation. Temporary support was incorporated between the abutment and the pier. The reinforced concrete composite haunch slab was cast on travelling formwork primarily at the midspans and subsequently above the piers. The construction was accomplished rapidly without any complications in the difficult access terrain. This proved the chosen steel concrete composite superstructure tangible, especially for the case of segmental launching construction.