Third of Works on Negrelli Viaduct Modernization Completed

The reconstruction of Negrelli Viaduct in Prague centre is entering its next stage. Works will start in the Vltava riverbed between the Bubeneč Riverbank and Štvanice Island inside gravel pits and on the scaffolding placed over them. In August, special foundation laying on jet grouting and anchoring of the support being demolished under the operating point in Křižíkova Street will be completed.

A part of the construction site in Prvního pluku Street was visited today by Mr. Dan Ťok, Minister of Transport of the Czech Republic, accompanied by Mr. Jiří Svoboda, Director General of SŽDC and Mr. Tomáš Koranda, Chairman of the Board of Directors of HOCHTIEF CZ. ”The viaduct is a unique historic landmark. We repair it very carefully in accordance with the preservationists’ requests and at the same time in such a way to increase comfort and safety of passengers on the railway. When the reconstruction is finished, people in Karlín will perceive lower noise from trains’ operation”, said Mr. Dan Ťok.

All original 99 arches are being rehabilitated; only two bridge constructions from a later period over Prvního pluku and Křižíkova Street will be replaced. During reconstruction, many non-homogenous parts and components differing both in construction and shape will be unified.

”The reconstruction will allow introducing a line speed of 60 kph. Line capacity will increase as well as considerable smoothness and number of trains being dispatched up to 14 pairs per hour. Modern safety and signalling technology will ensure safer operation”, added Mr. Jiří Svoboda, Director General of SŽDC.

Work shall begin gradually on rehabilitation of particular arches to include local changes of degraded masonry elements with a whole arch going to be re-bricked in case of large extent of damage occurred and with original material intended to be used to the maximum extent possible. New draining of space between arches and waterproofing insulation to copy the shape of arches will be carried out upon repairs of particular arches. The space between arches will be filled in by pervious concrete and a newly created flat surface will be laid down by a new reinforced steel support plate to hold additional structures. Three pillars had to be dismantled down under the terrain level at Štvanice Island.

”The reconstruction is going on for a length of almost 1.5 km. A complete exchange of railway superstructure including technological parts will occur as well as rehabilitation of foundations and subsoil by grouting, jet grouting and micropiles, all 99 brick, sandstone or granite arches will be reconstructed from which 8 span over Vltava River“, said Mr. Tomáš Koranda, Chairman of the Board of Directors of HOCHTIEF CZ about the reconstruction..

5 bridge structures span over Prague roads from which 2 will undergo a change of bearing construction (Prvního pluku, Křižíkova) and 3 will be reconstructed (Pernerova, Rohan Riverbank, Bubeneč Riverbank). Outdated safety and signalling equipment will be replaced by a modern electronic one and 3.3 km of rails will be exchanged. The improvement will be perceived by inhabitants in the nearby densely built-up area as laying anti-vibration mats and installing modern switch points will allow a decrease of noise from operation on the viaduct.

The area under the arches is considered for cultural and social use in the future which will improve the architectonical design of the Prague quarter of Karlín. The new railway superstructure will result in higher travelling comfort by form of a calm and smooth ride. This is also important as the construction will be part of the project in preparation which will ensure a railway connection to Václav Havel Airport.