“Currently, we only have an invalid building permit. We will get the final one by the end of the year, then in the spring. All you have to do is get it, so the contractor will be able to start building in a matter of weeks. Now it mainly depends on the settlement of objections, otherwise there is nothing to wait for. Each annual postponement of construction for inflation alone costs Prague two billion crowns, “said Daniel Šabík, head of communication at the transport company (DPP).

According to CEO Petr Witowski, DPP is also preparing a contract for the construction of another section in Nové Dvory. From June 2019, geological exploration will continue at the place where metro trains will run without a driver. Within it, half the profile of the tunnel for the metro is excavated somewhere, in the vicinity of the critical intersection with line C, it is even planned to excavate a “reconnaissance” tunnel in the entire profile.

Road in a cage

The editors of MF DNES went to the site to ensure what it looks like on the construction site now. However, escalators are not yet leading to the future D-metro tunnel. The path leads along a ladder or in a cage lowering crane – this is Due to the 36-meter depth of the mining shaft a more acceptable option.

An immovable witness to the geological survey is the statuette of St. Barbara hung on the wall of the shaft. “Barborka is a necessity, it is found in every mining work. She’s a patroness. He puts himself in a place where he has a view of the workplace and oversees safety. To protect anyone who comes to the mine with good intentions, “long-term construction manager from Hochtief Radek Kozubík.

And so, with good intentions, we set out to meet the more than 300-meter tunnel from the cemetery in Na Strži Street towards the future metro station D – Pankrác, which will be only 13 meters below the level of the track of the same name of line C. tunnel, which is excavated in these places by excavators using the so-called new Austrian tunneling method. The connection of the embossing shield is only planned in other sections of the construction. What we see is far from definitive – it will not be enough just to set off and lay the tracks. “It will have to be re-concreted and re-insulated, among other things,” Kozubík was the result.

Praguers have a living memory of the Blanka tunnel, which took place in Stromovce in the Ministry of Culture. Since then, Prague has not underestimated the larger underground structure, as evidenced by a detailed geological survey on line D. According to current findings, all work will have to be carried out with the utmost caution.

“Geology is specific in Prague. It affects how fast the work can progress, the construction technology or the amount of usable building material needed to anchor and secure the work, ”says the construction manager.

Geological surveys took place in a total of four places of the future metro D. Two lasted a year and have already ended. The survey is more extensive at two locations, between Na Strži and Pankrácí streets and at the intersection of Budějovická and Na Strži streets. It was originally supposed to end at the end of the holidays, but the work dragged on, the survey definitely ended at the end of this year.

“In lengths of eighty meters, different positions of slate alternate here. Each layer has different geological parameters. It was necessary to determine their interfaces and parameters that will be necessary for the implementation of large constructions, “the result of Kozubík.

Subsequent dewatering, according to Šabík, quickly overlaps the structure of the overburden. “Thus, there could be a shift in the order of centimeters, which would be essential for the operation of the line tunnel of the existing C lines and the surrounding engineering networks. That is why we need to stabilize the overburden and we need to dismount, “says the head of DPP communications. According to him, during the geological survey, about 30,000 cubic meters of rock were mined, which is about three thousand trucks. To stabilize the walls of tunnels and shafts, we need about eight thousand cubic meters of shotcrete.

Work nonstop

Our walk through the exploration tunnel ends after 280 meters, even though it is exactly 322 meters long. In the last part, it is just turned off the fresh air supply and due to the noise of construction work, you can not hear your own words. If the technology was switched off, according to our guides, we could hear trains in metro C passing a few meters above us. There are several workers around us, who take turns here in two shifts 24 hours a day, seven days a week.

The day when we will be able to ride the first section of line D for the first time is irresistibly approaching. The exact term is affected by many circumstances, but it could still be during the current decade.