At 11 km long and with a roof with a light show, China’s longest underwater tunnel has become a tourist attraction

Under the waters of Lake Taihu, in the Chinese province of Jiangsu, lies the longest underwater tunnel ever built in China. Although it serves today as a great solution to decongest one of the most dynamic regions in the country, it has also become, almost by surprise, a tourist destination on its own merits. The reason: a majestic ceiling full of LED lights that change color and an architecture almost designed more to be contemplated than to be functional. A key point. As we mentioned, the tunnel extends under Lake Taihu, in Jiangsu province, about 50 kilometers east of Shanghai. It aims to connect the expressways of Suzhou, Wuxi and Changzhou to relieve traffic pressure in the lakeside cities, while also serving to boost economic development from the Yangtze River Delta region. It is also a segment of the highway that connects Shanghai and Nanjing, the former national capital. For this reason, it is a key piece in China’s infrastructure network, but its design and light show have also led to it being transformed into a whole tourist experience. Figures. With 10.79 kilometers in length, the tunnel had a cost of about 9.9 billion yuanabout 1,230 million euros. Work began in 2018 and lasted almost four years. To build the two-way tunnel, with six lanes and 17.45 meters wide, more than two million cubic meters of concrete were used. For ventilation, there are three complexes distributed along the surface of the lake that guarantee air circulation inside. The challenge of building under the mud. It was not a simple work. The bed of Taihu Lake is formed by large accumulations of clayey silt, which made it impossible to use conventional excavation methods with tunnel boring machines. The engineering team opted for a cofferdam system: the route was divided into nine sections and, in each one, a temporary dike was built to “create solid ground” and work dry. Once that section was finished, it was filled with water and moved on to the next. According to collect Tunnels & Tunnelling, one of the biggest challenges was waterproofing the structure, since at some points the tunnel is 20 meters below the lake bed. Thes LED lights yesThey always improve everythingeither. Their figures and the work that had to be done for something of such magnitude to materialize is impressive. But the tunnel has attracted more and more attention for a clear reason: its roof. Those responsible They installed LED lights on the roof of the tunnel to combat driver fatigue during what would otherwise be a very monotonous journey underground. The panels do not simply project a uniform color, but rather show images that change. Ventilation and architecture. But the LEDs on the ceiling are not the only eye-catching element. The three ventilation points that emerge on the surface of the lake have been conceived as sculptural pieces. According to China Dailythe one located in the center of the tunnel was transformed into an artificial island 150 meters in diameter; that on the western side, near Mashan, is shaped like a conch; and the one on the eastern side, next to Nanquan, evokes the silhouette of an ancient boat. The most striking is the one known as “Jade Snail”: 45 meters in diameter and 39 meters high, it is equipped with 174,000 LED light points. A tunnel that generates tourism. The CCCC construction company points out that the Taihu tunnel is now the second highway between Shanghai and Nanjing, and has increased the number of visitors to the tourist enclaves of Lingshan and Nianhua Bay by 50%. The Mashan area, directly connected by the tunnel, is home to the Lingshan Great Buddha, one of the largest in the world and a pilgrimage destination for millions of people. Liu Xiaoyu, head of Wuxi National Taihu Lake Tourism Resort, pointed out told China Daily that “the tunnel will bring more tourists to the Lingshan Scenic Area and hotels in the area.” recordd. At almost 11 kilometers, the Taihu is the longest underwater tunnel in China, but it is not the first in the world. The title of longest underwater road tunnel remains with the Norwegian Ryfastwith 14.3 kilometers, connecting the city of Stavanger with the municipality of Strand. On the other hand, if we talk about underwater tunnels in general, the Eurotunnel (which links England and France by rail) retains the absolute record with 37.9 kilometers of submerged section. Images | CGTN In Xataka | Xiaomi or Xpeng car factories are so advanced that they have become the favorite destination of Chinese schools

China is building a tunnel under the sea for its high speed. It has already reached a record depth

Under the seabed, dozens of meters deep, there is a work that is progressing with a minimal margin of error. It cannot be seen from the surface, but it is part of a railway infrastructure key in southern China. According to CGTNthe country has reached a new milestone in the construction of a high-speed underwater tunnel: the excavation has already reached 113 meters under the seabed. The figure is not minor, because it places the work at a point where the geological conditions and water pressure significantly increase the technical difficulty. This advance is part of a much larger infrastructure that is taking shape in the south of the country. The 116-kilometer Shenzhen-Jiangmen high-speed line is designed to connect both cities in less than an hour, integrating into the rail corridor that runs along the Chinese coast. In this way, the project has entered a particularly demanding phase, in which the tunnel under the Pearl River estuary becomes one of the most technically complex points of the entire work. A section under the sea that concentrates the greatest technical challenge At the center of this phase of the project is the underwater infrastructure that requires refinement of each step. To execute it, the work relies on a large diameter tunnel boring machine developed in China. The machine, known as “Shenjiang-1”, has kept the excavation going continuously, even during festive periods such as Qingming. It not only drills the ground, it also allows progress while the interior lining of the tunnel is being built, a system that seeks to gain efficiency in one of the most delicate points of the route. From there, the challenge stops being just mechanical and becomes conditioned by the terrain. The TBM must traverse 13 different strata, with five types of composite geology and six fault zones along the route. These types of conditions force the operation to be constantly adjusted, because each layer can respond differently to the excavation. In this context, moving forward does not depend solely on the power of the machinery, but also on maintaining control in a challenging environment. Added to this complexity of the terrain is a less visible, but equally determining factor: the pressure of the water at those depths. The tunnel is planned to reach a maximum of 116 meters below the seabeda level at which hydraulic conditions become especially demanding for the machinery and the structure itself. To operate in this environment, the system uses a sludge circuit that fulfills a double function: on the one hand, it reduces friction at the excavation face and, on the other, it transports the extracted material to the surface, where it is separated and reused in the process. While the machine advances, the tunnel is not far behind. Just behind the excavation face, the teams are assembling the prefabricated concrete segments that form the interior lining. Each one measures around two meters wide and nine are needed to complete a ring in a structure that exceeds 13 meters in diameter. This system allows excavation and construction to progress at the same time, reducing time and helping to maintain the pace of execution. The magnitude of this work is better understood when put into perspective. Official information indicates that this section extends over 13.69 kilometers and crosses several waterways at the mouth of the river, located between Dongguan and Guangzhou. It is a key piece within a line designed to improve the connection in the Guangdong-Hong Kong-Macao Greater Bay Area. Beyond the depth already achieved, the project seeks to strengthen regional connectivity and support economic integration in one of the most active areas of the country. Images | CGTN In Xataka | Singapore is literally coming into its own: reclaiming 25% of land from the sea and turning wastewater into drinking water

China has been pushing the boundaries of engineering for years. Its gigantic high-speed tunnel boring machine has just given another example

China has been developing large infrastructures and its own machinery to execute them for years, with projects that tend to stand out for their size and the technical control they require. It is not just about building more, but about doing so under increasingly demanding conditions. This pattern is repeated in very different areas, from energy to scientific research, and also in transport infrastructure. Under this logic, the appearance of new machines and projects is not an exception, but rather the continuation of a clear trend that now adds a new chapter with the “Linghang” tunnel boring machine. The advance. “Linghang” has completed the section under the Yangtze Riverwith a continuous excavation of just over 11 kilometers, according to CCTV. The machine began its journey on April 29, 2024 from Chongming Island, in Shanghai, and after 23 months of work, it completed the underwater section of the river, surpassed the south dam and came ashore in Taicang, in Jiangsu province. The movement is not minor: it involves completing the section under the watercourse, one of the key points of the work, and leaving the project one step away from its next milestone. What’s behind. The operation is integrated into the tunnel Chongming-Taicanga key work within the Shanghai-Nanjing section of the Shanghai-Chongqing-Chengdu high-speed corridor. With a total length of 14.25 kilometers, this infrastructure brings together several technical milestones, including the world’s longest single head excavation distance in a high-speed tunnel, with 11.32 kilometers, and a maximum depth of 89 meters under the Yangtze. The design contemplates the passage of trains at 350 km/h even in the underground section. The machine inside. The tunnel boring machine used in this project has unusual dimensions even within this type of work: it measures about 148 meters in length and weighs around 4,000 tons. according to Global Times. It is equipped with an intelligent control system called I-TBM, designed to automatically manage a large part of the excavation process, from internal pressure to the forward position or the exit of the material. Added to this are elements such as high-pressure seals, a long-lasting main bearing and a cutting head prepared to withstand demanding conditions under the river. A project that is not an isolated case. In recent years, the country has built facilities such as the Three Gorges Dam, the FAST telescope either the EAST reactorprojects that, although they belong to different areas, share the same base: scale, technical control and own development. In this context, this type of machinery is best understood not as a specific milestone, but as one more piece within a sustained line of work. A close reference. In Spain, the Mayrit tunnel boring machine, currently in use in the expansion of line 11 of the Madrid Metrooffers a useful point of comparison to understand the magnitude of this type of machinery. Measuring about 98 meters in length, weighing around 1,500 tons and with a diameter close to 9 meters, it is a large piece of equipment within the European context. Images | CCTV In Xataka | Czechia wanted to build a highway and found a problem: an intact 2,000-year-old Celtic city

If the question is who is going to illuminate part of the new A-5 tunnel, the answer is simple: the sun

He burial of the A5 continues its course. It is one of the most ambitious works in the recent history of the Spanish capital and, after months of headaches, you can see the light at the end of the tunnel. There is still a way to go, but the light thing is quite literal if we take into account that, in the surface park, there will be enormous pergolas that will not only serve to provide shade. They will be the battery of the tunnel. The pergolas. From the beginning The project took into account the installation of an infrastructure that would allow the use of sunlight to power the tunnel through which the vehicles will circulate. The idea with this burial is to create a large green area of ​​80,000 m2 that, in addition to trees, will have another solution to shelter pedestrians: eight pergolas to combat the sun and rain. They won’t be the only thing they will do. As the Urban Planning, Environment and Mobility area of ​​the Madrid City Council has commented to ABCall of them will have photovoltaic panels that will total 1,055 panels for a nominal power of 437 kW and an annual production of 561 MWh. It is the equivalent of the annual consumption of 200 homes in Spain and the energy that will power the installations of the underground section. We will see when the works are completed, since the Madrid City Council already calculation a production of 1,158 MWh per year. Geothermal. All the pergolas will not be the same and the panels will be installed in the most optimal way possible to meet this estimated production, but it is not the only system planned to supply the park facilities with electricity from renewable sources. An example is the Ángel González Municipal Public Library, located at one end of the project. Currently, and as detailed the town hall, the thermal installation compose of a 285 kW boiler and a 220 kW chiller. In their place, two 150 kW heat pumps will be installed and will employ low temperature geothermal energy to create a water circuit tempered at a constant 25 degrees. It is a form of renewable energy that takes advantage of the constant heat of the shallow subsoil to air condition buildings and produce hot water. Undertaking work to switch to low-temperature geothermal is a complex and expensive process, but on the scale of the A5 underground, it makes a lot of sense. In this way, a pump will exchange heat with the ground to extract ground temperature in winter and, in summer, transfer heat from the building to the subsoil and, thus, cool the library. All this without local combustion. Mountains in the capital. And since we’re talking about renewables and reusing, it’s curious what they will do with some of the land they are excavating. Instead of having to manage it as waste, in part of the walk will be created three artificial hills. It is a good way to take advantage of surplus land, but it will also have a useful function. They will house thousands of trees that must be relocated due to current works, but, in addition, each of the hills will have a purpose. One will be a park with picnic areas and biodiversity areas, another will house a skatepark and another will become a viewpoint. Let them finish now…That is the feeling of the neighbors who have been enduring headaches from noisebut also an urban ‘Mario Kart’. Because it is very good to undertake works that use renewable energy to solve specific problems, but it is normal that there are those who are choking on these works. In the end, it is not easy to cut one of the access arteries to the city for almost two years to bury 3.2 kilometers of a highway on which 80,000 vehicles circulate a day. There is less left until the end of 2026… Images | MadridMadrid City Council In Xataka | Madrid wants to put 110,000 tons of weight on the M-30. And the challenge is not technical: it is not to collapse the road

To no one’s surprise, the fanciful tunnel that aspires to join the Strait of Gibraltar under the sea will not be ready by 20230

The idea of ​​connecting Europe and Africa with a direct channel that allows us to do without ships and planes is so attractive, so damn sexy, that it takes more than a century warming the imagination of engineers. The same time they have been seeing the Strait of Gibraltar as the ideal point for a Spain-Morocco tunnel. After decades of idling, in recent years the project seemed gain momentumat least as far as the political sphere and the public interest. A few months ago even transcended that one of the leading companies in tunnel boring machines sees the infrastructure as technically viable. He hype around the tunnel it grew so much (and so strong) that there were those who trusted that the 2030 Soccer World Cupcelebrated mainly in Spain, Morocco and Portugal, it would serve you of ultimate lever. They were even read headlines that suggested that it would be executed with a view to 2030. To no one’s surprise, everything indicates that it won’t be like that. Strait Slopes. About a century ago, around 1929engineer Fernando Gallego Herrera a question was asked: Why not ‘suture’ the gap between Europe and Africa with an underwater tunnel in the Strait of Gibraltar? He was not the first to consider the issue, but he did so with a seriousness, a degree of technical level and a vocation, which gave visibility to the approach. Since then the idea of ​​creating a megastructure that allows Spain and Morocco to ‘touch each other’ has continued with comings and goings on the table. And not only on a theoretical level. The idea of ​​establishing a “fixed link” between Spain and Morocco even led to the creation of two entities: SECEGSAon the Spanish side, and the Societé Nationale d’Etudes du Detroit (SNED) on the Moroccan side. In recent years, the project has also attracted headlines that echoed the degree of political commitmentthe investment in studieshis time horizon and even his technical feasibilitya key aspect considering that we are talking about a structure of several dozens of kilometers in a difficult geological area. A small (big) step. In 2024 the project gave one step forwarde that (although very initial) was revealing. At the request of SECGSA, INECO commissioned a study for the “cross-strait fixed link project”. Its objective was basically to analyze “the feasibility” of excavations in the area, especially in the most critical points, such as the Camarinal Threshold that separates the Mediterranean and Atlantic basins. The task fell to a famous company in the sector: Herrenknechta leading German firm in the world of tunnel boring machines related, among other works, to the Brenner Tunnel or that of Saint Gotthard. Viable yes, although not cheap. The conclusions of their analysis have been known in recent months. First in October Populi Voice revealed that the German firm has confirmed that, although extremely complex, the Spain-Morocco pipeline would be viable from a technical point of view. The same media reported that the purpose of Spain and Portugal would be to decide in 2027 whether or not to tender an exploratory tunnel and provided a provisional calendar: just shaping the reconnaissance gallery would require between six and nine years. Regarding the cost of infrastructure, slid that the base bidding budget of the Spanish side would exceed 8.5 billion euros, a figure that includes everything from the base gallery to the tunnels, the terminal and other facilities. The sum is considerable but there is talk of diversifying its origin, including everything from community funds to formulas (concessions, fees) inspired by other megaprojects, such as the Eurotunnel wave Figueras-Perpignan line. Has there been more progress? It seems so. Although again in an initial phase still. At the end of November Populi Voice revealed again that, after the technical endorsement of Herrenknecht, SECEGSA entrusted INECO to complete the updating of the preliminary project of the structure. A deadline was even included: summer 2026. Around the same time, the Government of Spain and Morocco held a summit in Moncloa during which a memorandum was signed to “promote scientific cooperation in the study of seismicity and geodynamics in the Strait area.” In the statement released by Transport there is no mention of the tunnel, but there were those who saw in the agreement a positive nod for infrastructure. Question of deadlines. The tunnel is not only interested in its technical details and cost. Another key aspect is your calendar. Especially since already in the autumn, when the first touches of Herrenknecht’s analysis became known, slipped that the first progress of the project could arrive by 2030, the year of the Soccer World Cup in which Spain and Morocco participate as host countries. The coincidence of dates made it create expectation about how the Cup could influence the project and even if it would act as a stimulus for the subway. It was even raised if I could arrive on time. In recent days those expectations have received a jug of cold water. One more and unsurprisingIn fact. Why’s that? Because 2030 is four years away. And that is a ridiculously short time for a work that, beyond being viable on a technical and logistical level, is more than notable in complexity. First for its ambition and dimensions (more than 40 kmbetween the underwater and terrestrial section). Second because it must be developed in an area highly conditioned by its geology. Although there may be some progress towards 2030, Populi Voice mentioned in October sources close to the project that pointed to 2035-2040 as a “more realistic horizon” to see significant milestones. The idea would be to have gallery design recognition in June to put out to tender the infrastructure starting in 2027. As a reference, the construction of the Eurotunnel (50 kilometers) required some seven years (from 1988 to 19949 and Saint Gotthard (57 km) around 17. Moderating expectation. In recent weeks (and days) media like Huffington Post The reason either ACE They have echoed, citing the technical feasibility study, that the tunnel between … Read more

The tunnel between Spain and Morocco seemed like a chimera. Now a tunnel boring machine manufacturer says it is viable

The idea of ​​connecting Europe and Africa directly is something that takes century and a half fluttering the mind of leaders and engineers. The simplest way would be to connect Spain and Morocco through the Strait of Gibraltar, and what for decades was considered a chimera due to its complexity, today is a little closer. And the company that would make the tunnel boring machine He defends that “it is viable.” In short. I told it Populi Voice a few days ago. Óscar Puente -Minister of Transport- and Karim Zidane -Delegate Minister of Investments, Convergence and Evaluation of Public Policies of Morocco- they met in Moncloa to discuss the infrastructure expansion plan of the North African country. Puente conveyed to the Moroccan minister the interest of the Spanish business sector in participating in an ambitious project that plans to expand its high speed network up to 1,300 km by 2040. The meeting discussed infrastructure such as ports and airports, but the strategic backdrop is the vaunted tunnel that links Spain and Morocco. Centennial project. The union of Europe and Africa through a direct connection between Spain and Morocco is something that comes from afar. The same thing happens with the ‘Peace’ project that aims to unite the United States and Russiabut as in the case of the tunnel with Morocco, it has not yet materialized. In 1869, the Public Works Council already tested the possibility of connecting both continents through Gibraltar. The proposal ended up in the drawer, but over the yearsdifferent technicians and rulers have rescued it with a “we could do this.” There is a clear commercial interest both in mobility of people (the “passage operations” add many vehicles crossing by ferry) as commercial (improvement in relations between the United Kingdom and Morocco, the country from which they buy fruit). “Viable“However, although with some plan in between, nothing was finalized. Something has changed: a German company called Herrenknech affirms that the tunnel is viable. They are not just any company: it is one of those that leads in the manufacturing of tunnel boring machines -or boring machines- and, after a feasibility study commissioned by the Spanish company SECEGSAhave stated that the project is “technologically viable” after the reactivation and promotion of a few years ago and socioeconomic analysis published in 2024. It really isn’t that much distance that would have to be covered. In other parts of the world, such as northern europe or in China, we see similar underwater railway tunnel projects of considerable length. The particularity of the Strait of Gibraltar tunnel is not so much the length (it would have to cover about 40 kilometers underground and underwater), but rather the characteristics of the territory. Characteristics: the tunnel profile would be the following: Distance between terminal stations: 42 kilometers. Total length of the tunnel: 38.5 kilometers. Length of the underwater tunnel: 27.7 kilometers. Minimum range at the lowest point: 175 meters. Maximum depth: 475 meters. Slope: 3%. Complex. The geology of the strait is very complicated because it has numerous areas of unstable clay, but also very strong marine currents and the presence of earthquakes. Any slight mistake when carrying out calculations or using unsuitable materials would cause a catastrophe. This is where Herrenknech comes into play as one of the few companies with the capacity to design specific machines that can operate in these conditions. Apparently, they themselves confess that it would be a challenge, but that a route through the Camarinan Threshold (which is longer than a straight line, but also shallower) could be done with current engineering. and expensive. Viable, yes, cheap… no. According to the information of Populi Voicethe base bidding budget corresponding to the Spanish part would exceed 8.5 billion euros. HE wait that part will be paid for with community funds thanks to concessions similar to those of the Channel Tunnel. And the international implications would be tremendous, linking Rabat and Madrid, directly, by train. It’s going to be long. For a time it was expected that the 2030 World Cup that Spain, Portugal and Morocco will co-organize was the catalyst for this project, but the times simply do not allow it. It would be extremely complicated for the tunnel to be operational by 2030 when we only have a “it is possible” from the company that manufactures tunnel boring machines and, in fact, the estimated deadlines speak of a tunnel within a decade or more. Now, what was considered a chimera for decades is now have a realistic performance goal between 2035 and 2040 is an important step forward. But there is a lack of work, money and crucial international coordination to achieve the objective of this tunnel between Spain and Morocco. The next step? Carry out new studies shared between countries on seismic activity, possible tsunamis and the behavior of the maritime corridor, as well as a technical planning which must be done before August of next year. What is clear is that it seems more viable than the dam-bridge that someone proposed a few years ago. Images | SECEGSA (2), Moncloa In Xataka | Modern tunnel boring machines are real monsters compared to those of 1950. The paradox is that they are just as slow

the longest railway tunnel in the world

Megastructures have a what-do-I-know-what-do-I-know-what makes us love them. It makes perfect sense: They are colossal works that humanity has been doing for millennia and in which we increasingly use more and more sophisticated machinery. There is also a certain sense of competition, and if a few months ago Europe boasted of longest railway tunnel in the worldtoday we have to talk about an even more difficult one: one twice as long and underwater. It is the Bohai Strait Railway Tunnel. AND will be in Chinaclear. Dalian-Yantai. To the sides of Beijing are the provinces of Liaoning and Shandong. The first has 44 million inhabitants. The second, 101 million. They are two important nerve centers in China, but there is a problem: they are separated by the Sea of Bohai and the only way to get from one to the other is by ferry, which takes about eight hours, or by going around the bay on a 1,500-kilometer trip. Given the importance that the area was gaining, in 1992 the idea of ​​a connection across the strait arose that would link the cities of Dalian and Yantai. Although China has accustomed us to mega constructions in record timein this case the logistics were complicated and it was in 2012 when a research group was established under the supervision of the Chinese Academy of Engineering to see if it was viable and, in 2019, they began to talk seriously about the project. Specs. A structure that combined bridges, islands and tunnels – like the Hong Kong Zhuhai-Macao– those in charge of the project agreed that the best solution would be a single railway tunnel whose characteristics are… colossal: 125 kilometers in total, 90 of them underwater. Designed for trains traveling at a speed of 220 km/h. Built 80 meters below the seabed. Two main tunnels of 10 meters in diameter. The most important thing: of the eight hours by ferry or more than ten by car, the journey would take about 40 minutes. It is a considerable reduction in time that will help not only transport people, but also what is most interesting in the region: goods and commerce. Train>car. The price of the tunnel has varied over long of these years. The estimate a decade ago was 200 billion yuan, about 30 billion euros. Currently, it is closer to 300 billion yuan, about 40 billion euros. Everything to unite two of the most powerful regions of China in terms of trade and more than the colossal Three Gorges Dam. HE esteem that it would take about ten years to recover the public-private investment in the infrastructure, and the reason why the tunnel has been planned as a railway tunnel instead of a mixed one (cars plus trains) is for safety reasons. Bohai’s will be more than twice as long as the Eurotunnelso creating such a long underwater tunnel suitable for cars would be extremely expensive and complex as it would require adequate ventilation. Furthermore, in the event of an accident, emergency response would be more difficult. What there will be are shuttle trains that will allow both cars and trucks to be loaded. This is something that is already being explored in other parts of the world and, recently, we have seen it raised in the American transcontinental. Challenges. Now, it’s not going to be easy. The topography of the bay bottom varies between areas of just 10 meters to others that reach almost 90 meters deep. In addition, there are active faults in the area and it is a region with high seismic activity. In fact, it is close to the Tan-Lu fault, one of the most active in China, which implies a thorough study to adapt the structure to possible earthquakes. Ecology. On the other hand, the ecosystem. Apart from being a sensitive area in terms of earthquakes, the tunnel would pass through ecologically sensitive areas. It is the habitat of the spotted seal, protected in China, and also includes migration routes for both fish and birds. You have to wait seated. And if we speak in the future it is because the works have not started. For now, it is about a projectbut in recent months important steps have been taken. In early 2024, the Bohai Tunnel was included in several national strategic documents, and in May this year incorporated to the Development Plan of the Modern Comprehensive Transportation System of the 14th Five Year Plan. In these 30 years, steps have been taken studying the feasibility of the project and exploratory drilling, and more recently more and more voices have emerged that mention the need to promote this Bohai corridor. When will the works begin? It is not known, but 2026-2030 is consider as the window of opportunity for it. Either way, if it ends up happening, Bohai will not only be – by far – the longest underwater railway tunnel in the world: it will also be one of the largest tunnels, overall. Images | Tambo, Ekem In Xataka | China has built the highest bridge in the world and has done what it must: turn it into a show

The enormous Mayrit tunnel boring machine on Metro L11 is already in Madrid. Now comes the real challenge: putting it together piece by piece

In Madrid there are already the pieces of one of the largest machines that will work in the city’s underground in the coming years. It is about Mayritthe EPB tunnel boring machine 98 meters long and 1,500 tons in weight whose transport started in Germany, continued along the Rhine to Rotterdam and continued by boat to the port of Santander. After that journey, a special convoy has completed more than 450 kilometers by road to take its modules to the future Comillas station, where it will prepare to excavate the new section of Line 11 between Plaza Elíptica and Conde de Casal. The work on which Mayrit will work is part of a broader intervention that the Community of Madrid describes in 2025 as the largest expansion of the Metro network in the last decade. Official data published in November put progress at 34% and maintain a budget of 518 million euros to complete the new section and the planned stations. The regional government maintains the year 2027 as a reference to close this phase of the project. Mayrit is already in Madrid: one hour left to convert its parts into a single operational machine When dealing with a machine of this size and complexity, each phase of the process requires precision that goes far beyond conventional engineering. Mayrit’s journey towards Spain began long before it appeared on the road: it started in Schwanau, the German town where Herrenknecht completed its manufacturing after about 20 months of work. There, more than a thousand kilometers from Madrid, the tunnel boring machine It was assembled for the first time in June 2025 to carry out initial verifications. This assembly showed the magnitude of the next step: converting the machine into a set of parts capable of traveling around Europe without risks. Disassembling it was not a quick procedure. For the next two months, Herrenknecht teams dedicated themselves to separating each module following a sequence calculated to the millimeter. The result was a set of sections ready to begin an international tour. The disembarkation in the port of Santander marked the beginning of the last stage of Mayrit’s journey, a phase that requires coordination very different from that of river and maritime transport. The pieces arrived distributed in separate shipments and were transferred to prepared platforms, a process that is carried out with specialized equipment to avoid any unexpected displacement. The organization of the road transfer incorporated common protocols in special transport, with large-tonnage vehicles escorted by technical teams in charge of checking clearances, turning radii and urban accesses. The authorities confirmed that the advance was carried out mainly at night to reduce interruptions and facilitate maneuvers in the most delicate sections of the route. The arrival in the Comillas area required a final deployment of personnel and machinery to accommodate each piece in the work area, where the assembly phase that will transform this set of modules into a single operational tunnel boring machine is already awaiting. The arrival of the pieces also marks the beginning of a phase that, according to forecasts distributed between June and November 2025, can extend until March 2026. Assembling a TBM requires joining modules in a strict order, connecting hydraulic and electrical systems, and performing tests that are concentrated between late January and February. It is a sequential process that is not resolved in a few days and that determines the date on which the machine will be able to start digging at the beginning of March. The official documentation describes Mayrit as an EPB machine adapted to the geotechnical characteristics of the layout. Its operation is based on maintaining a balance of pressures that prevents unwanted movements on the surface, especially relevant in urban environments. To sustain this process, shifts of specialists are involved who manage the control and evacuation systems of the excavated material. The expected performanceclose to 15 meters per day, will be decisive in setting the pace of mechanized advance. Comillas will be the point from which Mayrit will begin the mechanized sectionaccording to the forecasts that the Community of Madrid has been detailing since June 2025. From there it will advance to Conde de Casalwhile in parallel the manual excavation of about 700 meters towards Plaza Elíptica progresses, started in September with a performance of close to 50 meters per month. The beginning of the excavation will mark the jump between the preparatory work and the actual progress of the tunnel that will transform this section of Line 11. With each meter excavated, the planned layout will get closer to its final shape and will allow the progress of the project to be measured more clearly. It is a significant element within regional planning to reinforce mobility in one of the areas with the most demand on the network. Images | Community of Madrid In Xataka | Malaga has become a magnet for the most luxurious yachts in the world: the latest, that of the co-founder of Google

a tunnel between Russia and Alaska

The United States and Russia are separated by the Bering Strait. Barely 80 kilometers of sea divide the two nations, but in the winter months, something curious happens: it is possible to go from the United States to Russia by walking on the waters. In the middle of the strait are the Diomedes Islands, and each one belongs to a country. When the sea freezes, the four kilometers between islands become a corridor what is illegal travel. Now, however, Russia and the United States are approaching positions to create a corridor between the two countries. A tunnel between Alaska and Chukotka in Russia. In short. US President Donald Trump has emerged as a key actor in two of the most important and media conflicts of recent times: the Israeli intervention in Palestine and the war between Russia and Ukraine. Whether it was a campaign to get the long-awaited Nobel Peace Prize or not, the truth is that Trump has convertedand has turned the United States, in a considerable entity in both conflicts. Maintains constant calls with Zelensky and Putinand after one with the Russian president, the idea of ​​physically connecting the United States and Russia has returned. After one of those calls, Kirill Dmitriev, director of the Russian Direct Investment Fund (RDIF) and the Kremlin’s special representative for international economic cooperation, launched the proposal in Twitter X: a 112-kilometer railway tunnel between both countries, in the Bering Strait and under the Diomedes. Dmitriev’s decision was not spontaneous and, according to him, the RDIF has been carrying out a feasibility study of the project for months based on previous experience connecting Russia and China over the Amur River. 150 years of projects. The idea is not new either. In fact, Dmitriev himself alluded days before ‘World Peace Bridge‘that was created in the Cold warduring the Kennedy-Khrushchev era, but the truth is that plans to connect both territories have been on the table since the 19th century. In 1890, an American governor proposed a railroad that would link the world and pass through the Bering Strait. Two years later, the designer of the golden gate He presented his idea, although the Russians rejected it. In 1904, American railroad entrepreneurs they returned to the charge with the idea, the tsar Nicholas II gave the go-ahead and then came the Russian Revolution and the World War I. He later explored the possibility of the connection again, but 150 years later, Russia and the United States still do not have their tunnel. The letter from “the boring company”. What could be the key now to undertake the works? Beyond the geopolitical card, the costs. In his proposal, Dmitriev outlined some of the results of that feasibility plan, stating that a tunnel in the Bering Strait would cost more than $65 billion if traditional methods are used, but (and here comes the “but”), another entity could lower the total cost of the project to less than $8 billion. Who? Elon Musk and his company The Boring Companionand. The Russian representative claims that the technology from Musk’s tunneling company (which built the The Loop tunnel in Las Vegasin addition to starring in several controversies for their projects) would allow not only to turn the project into reality with a low budget, but to do so in less than eight years. frozen enemy. The problem, if all parties agree, is that the soil in Las Vegas is not the same as that in the Bering Strait. At 112 kilometers in length, the tunnel would be twice as long as the Eurotunnel between France and England and, furthermore, it would have to be excavated in very complex terrain. To begin with, the region is located in the Pacific Ring of Firean area with moderate seismic activity, but where earthquakes of magnitude seven can occur. In addition, it would have to be excavated 45 meters below the seabed to protect from currents and, most importantly, the entrances to the tunnel would be in permanently frozen ground. If everything remained unchanged, it wouldn’t be much of a problem, but Alaska has experienced a increase in average temperature during recent yearssomething that is expected to continue due to climate change, and melting ice would complicate maintenance of these parts of the tunnel. In fact, it’s already happened on the Trans-Alaska pipeline. We will see if this project comes to fruition or if it ends up on the list of “we should make a tunnel”, but the truth is that there are too many against it, starting with issues of national security, geopolitics, the terrain itself, the extreme geological conditions and even the train connections that would have to be made through Alaska and Russia for the tunnel to be of any use. In Xataka | In June, a resident of a tiny island in Alaska saw a rat. Since then there are 400 people looking for her like crazy

A 1,500-ton tunnel boring machine is already traveling to Madrid to drill the new Line 11

“Notify when you leave and when you arrive” Mayrit has already done the first. The second will be in more or less a month when all the pieces are already on Spanish soil. Mayrit is not the youngest son of a family. Mayrit has many fathers and mothers. Many. Those necessary to give life to a 1,500 ton tunnel boring machine. That tunnel boring machine that will directly expand line 11 of the Madrid Metro. A line that, until now, has been excavated with much more traditional means and that of course will take a huge leap forward in its future projection with this gigantic and enormous artifact. What’s coming, what’s coming Connecting Cuatro Vientos, southwest of the capital, with Valedebebas, northeast of it, Line 11 wants to become in one of those star connections in Madrid. Tracing a diagonal, the intention is to convert what is currently just seven stations into one of Madrid’s great corridors. The qualitative and quantitative leap in the progress of the works will be made by Mayrit. This gigantic tunnel boring machine weighs 1,500 tons and is 98 meters long. It is expected that each day about 15 meters can be advanced on the land, key in a line that will have stations 33 meters below ground from Madrid. My colleague Javier Márquez explained a few months ago that the transfer is not easy. The machine is built by Herrenknecht AGa German company that has assembled the entire gigantic puzzle of pieces, screws and components in its country. Once assembled, the machine is cut into pieces to be sent to our country. Of course, “it won’t be quick or easy,” as my partner explained. Now we know that the powerful tunnel boring machine has already set out on its way to Spain. It comes by land and sea. And the bulk of its pieces will arrive in Santander by boat where they will board land transport to reach the capital. Another good package of these pieces will arrive at the port of Valencia, originating in Venice. Map of the new Line 11 Once the pieces arrive, they must be transported to Carabanchel. There, next to Plaza Elpítica, this monster will drill into the ground at a rate of 500 meters per month to connect with Conde de Casal, about six kilometers from the point of origin. This stage is considered one of the most problematic and complex. Until now, the connection between Parque de Comillas (which will have a new station) and Plaza Elíptica is being done by hand. However, the transfer and assembly is so delicate and complex that it will not be until March 2026 when everything is expected to be ready in the Madrid neighborhood to begin drilling the ground. The system is so complex because the tunnel boring machine is not only responsible for excavating the earth and disposing of what is found there. While working advancing into the subsoil, an auger transports the excavated material with a conveyor belt. This material can be washed if it encounters mud but it can also affect the stability of the ground with injections of bentonite, water or foam. All while sensors control the pressure the machine experiences to control how fast it can work. If everything happens according to the planned deadlines, the last piece from Mayrit should arrive in December and, as we said, it is not expected to come into operation until March 2026. For now, it’s time to pull the shovel and pneumatic hammer. Photo | Madrid Metro In Xataka | Faced with daily collapses, the Madrid Metro could increase frequencies or put in “pushers.” He has chosen the second

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