Hlubočepy – Barrandov Tram Line, Phase II

The elevated tram line in Hlubočepy

(467 m) is a bridge comprising of 11 spans, with the bridge floor made of a reinforced-concrete continuous pre-stressed beam of a built-up box section, laid out as an arch, transition curve and straight. The maximum longitudinal slope of the bridge reaches 6.2 %, the one-sided cross gradient of the bridge floor is 2 %. Taking into account its layout, the beam was produced by combining various technologies (the bottom part by its positioning on a fixed centring, the upper part by gradually drawing out – lowering reinforced-concrete segments from the “in situ” production plant located behind the closing wall of the upper abutment of the bridge). The basic structure is made up of reinforced-concrete pillars of 2.7 m in diameter (the largest of them is 19 m high), which change into a n oval cross section in the head ( in the transversal axis). The basic structure is founded in a combined manner – on piles, micropiles and shaft piers. The cross profile of the bridge floor is completed with rail prefab bracing pieces to its total width of 11.7 m.

The elevated line across the Růžička Gully (Růžičkova rokle)

(294 m) is a bridge comprising of 7 spans. The bridge floor is the same as the one applied on the first bridge, laid out as an arch, produced by gradual drawing out –  lowering reinforced-concrete segments from the “in situ” production plant located behind the  closing wall of the upper abutment of the bridge. The basic structure is made up of hollow reinforced-concrete pillars of a 3.4 m external diameter with an oval head as in the case of the Hlubočepy elevated line, of the maximum height of 32 m. The basic structure is based on piles and shaft piers with the maximum depth of their foundation of 33 m and a special finishing of the foundation bottom to speed up the consolidation by means of pre-stressed reinforced-concrete blocks. The cross profile of both bridges is the same.

The inner space of both bridges (and boxes) as well as of the adjacent reinforced-concrete structures is used for power supply network cabling. Both reinforced-concrete bridge girder systems are monolithic, produced as fair-face concrete and covered with protective paint. To protect the bridge floor, gravel insulation on the basis of modified bitumen with reinforcing was used.