The long history of works on line 9 of the metro is made up of a cluster of delays. Two years after the reactivation of the tunnel boring machine after eleven periods of paralysis, it is time to add a new obstacle that has already caused the Generalitat’s plans to open the central section of the L9 in 2027 to go to waste.
The tunnel boring machine has been stopped since the end of February about 500 meters from the future Mandri station and will continue there without moving for a few more weeks. Until the end of May, as soon as possible. Greater than expected wear on the cutting wheel has forced those responsible for the project to stop the progress of the machine. For more than a month the operators have been replacing the teeth of the front shield, since in the current state it was impossible to continue, as La Vanguardia has learned.
“It is a stop that has been decided after encountering more difficulties than expected due to the type of terrain”, acknowledge sources from the Department of Territory. The problems appeared when the apparently most delicate part from the geological point of view had already been overcome. Now all that is left in front of him until he reaches Mandri is granite, a very stable material for the TBM but which at the same time means significant wear and tear due to its hardness.
The goal of those responsible for the work is to get the tunnel boring machine ready in the coming weeks so that it is able to excavate the remaining half kilometer from the place where it got stuck to the well at the Mandri station. It should have arrived here at the end of last year, if the forecasts announced last summer by the president of the Generalitat, Pere Aragonés, and the minister of territory, Ester Capella, had been fulfilled during a visit to the works .
The new deadline set to reach Mandri is during the summer, if nothing goes wrong again. It will then be when a much more complete set-up will be carried out to culminate with all the guarantees the remaining 1.6 kilometers of tunnel to Lesseps station. The achievement of the goal was scheduled for the end of 2024, although the unexpected that they have now encountered has thrown the calendar into disarray.
The Department of Land avoids setting new dates for this milestone and, therefore, for the completion of L9. They condition everything on a deeper analysis of the machine when it arrives at the Mandri well. And, what’s more, they try to take responsibility off of themselves by remembering that “the tunnel boring machine was stopped underground for eleven years due to a political decision and, although maintenance work was carried out, it is not a new machine”.
Hospi, which is the name of the tunnel boring machine that is drilling the underground of the upper part of Barcelona, ??is the last survivor of the five tunnel boring machines that have worked since 2002 on the L9 works. Twelve meters in diameter and 100 meters long, it weighs the equivalent of four gigantic A380 planes, the largest model that can be seen at El Prat airport.
During the eleven years that it was unemployed, it underwent conservation work that cost 7.5 million euros to prevent it from being damaged the day it returned to work. When the day came, after several months of fine-tuning, it was confirmed that it was in good condition to finish the jobs without having to resort to a new machine. In the spring of 2022 it was back to work 24 hours a day and at first it even worked better than expected, advancing about 200 meters per month. Recently, however, the pace had slowed down. Already last summer it had to make a maintenance stop (in this case it was pre-scheduled) when it had not yet arrived in Sarrià. Having passed this station during the second half of last year, it has been progressing little by little until it finally got stuck about 500 meters before reaching the Mandri well.
Both in this future station and in Sarrià, work continues despite the shutdown of the tunnel boring machine. The Mandri well has been finished since December, waiting for the tunnel boring machine to arrive and cross it, even if this cannot be seen by residents and pedestrians. Yes, the works on the future lobby and the station’s emergency exit are more visible, which has forced traffic on Carrer Mandri to be cut off and is the first thing patients see when they leave the eye surgery clinic there right on Paseo de la Bonanova, right in front of the works.
In Sarrià, on the other hand, a little more than 60% of the 72 meters deep well has been excavated. It is planned that during the second half of the year the connection gallery between the well under construction and the tunnel will begin to be executed.
