By T.R. Witcher
Mexico City's new baseball stadium melds a structurally airy roof with a base inspired by traditional Mexican architecture.
The new baseball stadium for Los Diablos Rojos del Mexico will feature a lightweight fabric roof that takes the shape of an arrow. © JAHN and ADG
January 27, 2015—Although soccer remains the national sport in Mexico and even American football is popular, baseball is cherished by the nation's working class, and a new stadium for the baseball team
Los Diablos Rojos del Mexico
, in Mexico City, is meant to provide a welcoming and accessible sports venue for both the capital and the country.
Before the advent of the stadium, the Chicago-based architecture firm JAHN had partnered with the Mexican architecture firm ADG on an unsuccessful bid to design a new terminal at Mexico City's Benito Juarez International Airport. The firms teamed up again to pursue the baseball stadium commission, which they ultimately won. Truth be told, JAHN's chief designer, Francisco Gonzalez-Pulido, a native of Mexico City, wasn't a big baseball fan, but having lived in Boston and now Chicago, he knew something about the typology.
"It made an impression on me, in my mind, how antiurban these buildings were," he says. "These building are like huge boxes that are not very porous, not very friendly in terms of urban connection. They're basically walls. That made an impression on me."
His first impulse, then, was to suggest a more open form. Unlike such sports as soccer, football, hockey, and basketball, in which the game's movement is bidirectional, one team advancing toward the end of the field and the other team advancing in the opposite direction, baseball was geared around decisive movement in one direction-namely, a baseball heading out of the park. He wanted visitors to enter the stadium along the same trajectory.
He also wanted that sense of direction to imbue the structure with a strong presence. He grew up in Mexico City and his father had a plane and took him on flights. The Mexico City of Gonzalez-Pulido's youth was not a city of skyscrapers, but of buildings at a monumental, horizontal scale—the Zócalo, the large public plaza in the center of the city, for example, or the large canopy protecting the courtyard at the Museum of Anthropology, or the National Auditorium.
The nine roof segments feature minimal support yet cantilever 15 m. © JAHN and ADG
"The building was always about this big figure that was recognizable from the air," he says. But it had to hold its own on the ground, as well. "The building had to have a strong profile, a strong presence, a lot of character."
Some have likened the form to a trident or devil's tail—a happy coincidence for a team named
—but the real motivator for the shape was the architect's desire to give the roof a sense of movement, direction, and visibility. Further, Gonzalez-Pulido wanted the stadium "very connected to modernism but very rooted in the use of materials [from] Mexican culture."
The roots of Mexican architecture are topographical and monumental, says Gonzalez-Pulido. The great ruins of the country are large and imposing places, "very geometric, very organized, very legible," he says. He wants the ballpark to have a similar sense of openness, of being a procession. "The building is almost like a temple. The way you enter the building is through this humungous ramp. Very processional. As you enter the building, the materials are very connected with what we identified as Mexico."
The trapezoidal elements of stadium's base will be formed with indigenous volcanic rock, its black and red hues matching the team's colors. Designers are still exploring ways to give the rest of the precast-concrete building a more rugged, raw appearance, possibly by mixing some of that volcanic rock into the aggregate.
In contrast to the heavy, rugged base, the stadium itself will be capped by a light and soaring roof, which will likely be clad in polytetrafluoroethylene (PTFE). Master engineer Stephen Hagenmayer, Dipl.-Ing, the general manager of the Stuttgart office of Werner Sobek, the project's engineering consulting firm, notes that JAHN wanted the roof to be "very, very slender." The challenge, he says, is to develop a steel structure that is stable enough "for the strong wind loads and earthquake loadings, while at the same time presenting a very slim side view."
The entrance to the ballpark is meant to create a strong sense of procession. © JAHN and ADG
Nine roof segments are planned, a central roof that forms the entryway to the ballpark, and four roof pieces flanking either side of the main roof, above the grandstand. The segments are around 20 m wide and between 80 and 100 m long, have cantilevers 51 m long, and they are supported by only three columns. "It's ambitious to have only three supports there," says Gonzalez-Pulido. "I want the roof to be a lantern as well—an urban lantern." The lighting will be integrated within the two layers of fabric making up the PTFE membrane. There are no light poles around the field; instead, all of the lighting is at the edge of the roof, which is why the roof angle is so high, 45 degrees.
The roof will pay dividends for patrons watching the game from the berm, the grassy back end of the stadium that seats 3,000. "I wanted them to have an experience to be looking at something that was beautiful, not simply a roof ring. This thing is so sharp," Gonzalez-Pulido says. "It's really coming at you. It's coming to get you."
The roof is a pure steel structure. "This is the key," says Hagenmayer. "No other material is capable of accepting those loads." The columns themselves are still being considered—they could be steel, or concrete, or a composite. "We are interested in having as little vertical dead load on the roof structure as possible," Hagenmayer says. "Because of the huge cantilever, the more load we have, the more difficult it is to make it a slender structure.
"The architects' intention is to have a flat surface on top of the roof structure," Hagenmayer continues. "This can be achieved by using metal sheeting or a membrane. The membrane could be placed on top of the metal sheeting or alternatively as a free-spanning skin. With the second option, however, you cannot work with a flat membrane, only with a double-curved one. In that case you'd need to have a membrane cushion on top or a membrane prestressed above a curved steel substructure. This solution would allow the constant draining of rainwater, thus preventing the forming of water skins and subsequent membrane failure."
To plan for the effects of both the weak soil and the area's seismic activity, Werner Sobek will conduct a "voluminous earthquake simulation" for the building. Engineers will build a complete 3-D model, including the structure's basement and cores, to determine where the stresses and forces will present themselves, then work through several iterations to determine how the stadium should best respond.
"I think we have to connect the single roof pieces together," says Hagenmayer. "If we keep them totally independent of each other, the deflections will be too high." The solution may be a semirigid joint that connects the roof pieces together while providing a little deflection.
The ballpark will likely be at the highest elevation of any baseball stadium in the world. "Winds are pretty significant, which is going to make the game pretty interesting," says Gonzalez-Pulido. And though high-elevation stadiums are typically thought of as a hitter's paradise (think of Coors Field in Denver, where the thin air allows balls to travel farther), Gonzalez-Pulido says, "We want to make it difficult for home runs."
The site is located in the sports complex of Magdalena Mixhuca, near one of the city's poorest areas. The new ballpark is meant to be a welcoming and "democratic" space, Gonzalez-Pulido says. Tickets will cost only $1. A parking garage is also planned beneath the field.
The project will also protect trees on the site and nurture a strong connection to its surroundings. To the southwest will be a secluded, tree-lined garden area that will feel, Gonzalez-Pulido says, like a picnic in the woods. The north side of the site is the formal entryway, the civic plaza, a place to celebrate the open and social nature of Mexican culture. It will also be a place for vendors selling all sorts of things.
To the southeast a more formal civic plaza is planned, with retail, food stands, and a baseball hall of fame. "Because of the location, we feel that place is where people will engage 24-7," says Gonzalez-Pulido. The plaza will also have access to the berm. "We want to make it very open to the public, very porous to the stadium," he adds.
The project is in the midst of schematic design now and is scheduled to open by 2017. The team will play in a temporary stadium until then. Architects often talk about the effect they hope their building makes on a community or city. Gonzalez-Pulido considers the stadium from the other end. "My biggest dream is to see what people are going to make with the building," he says. "How the building is going to be transformed by Mexicans—this is my biggest ambition for this project."