In Spain, soccer stadiums are often as beloved as their local teams. The Carlos Tartiere stadium in Oviedo, a small city in the northern Asturias region, is no exception.
Built in 2001, the Tartiere stadium is home to the city’s Real Oviedo soccer team, a second-division club that’s been engaging fans for 95 years. As one of the most important clubs in the region, loyal supporters fill the 30,000-seat venue to near capacity on match days. And as they’ve watched the games, they’ve also witnessed the creeping deterioration of the stadium.
Rectangular in construction, the Carlos Tartiere is made of reinforced concrete that stretches 180 meters long and 100 meters wide. Standing 40 meters high, the structure is topped by a partial, open-air roof comprised of reinforced steel beams covered by a sheet of metal. Over time, water has leaked through small holes around the screws affixing the roof, rusting beams and seats.
As both a Real Oviedo fan and an engineer, the stadium wear was not lost on Víctor Nicieza.
“Soccer is the most popular sport in Spain,” says Nicieza, an engineer with Simetría Gestion, a local engineering architecture firm. “Like the club teams, stadiums are a source of pride for the fans, the players and the city. On match days, there’ll be nearly 25,000 people in the stands, so it pays to maintain and upgrade these significant sources of entertainment and revenue.”
As a local government asset, the Oviedo city council recognized the stadium could become a safety risk and issued a call to assess the damage. The council wanted to understand what assets were impacted, to what degree and what solutions could resolve the problems.
A specialist in 3D modeling, Simetría Gestíon viewed this invitation as a chance to show the public authority how laser scanning is viable for assessing structural damage. In addition, the 3D imaging could inform a refurbishment plan and long-term maintenance program.
“Because the stadium is the city’s responsibility, they have to justify any costs related to its repair,” says Nicieza. “So they need to have accurate details on what exactly needs to be fixed or replaced and what that will cost. With 3D laser scanning, we knew we could clearly and precisely pinpoint areas of risk, show them how to measure that risk and then calculate the costs from that.”
Nicieza and his engineer colleague Eduardo Alonso took their Trimble X7 scanner to the stadium in November 2020 to capture one upper area that covers three seating sections where the structure had weathered significantly. The X7 is a sophisticated, yet simple scanning system that offers survey-grade self-leveling and automatic calibration, and automatically registers scans in the field.
Setting up the X7 for their first scan, they used Trimble Perspective field software to tie into three existing control points to correctly position the point cloud. They then scanned their way from the field to the upper seating rows to collect every visible feature of the structure. Each time they moved to a new position, the X7 automatically leveled and calibrated itself and the Perspective software automatically registered each scan, allowing the team to review each one in 3D before moving on.
The team completed 44 set-ups, including five from a narrow platform just below the roof. In five hours they captured 753 individual roof beams and 80 million 3D points.
“Two of the biggest benefits of the X7 are its self-leveling and automatic scan registration,” said Nicieza. “The ability to set it down and start scanning in seconds, automatically register the scan and then check it right there saves us hours in the field. And it ensures we capture all the features we need the first time.”
After refining and coloring the data in Perspective, they imported it into Trimble RealWorks software to create a point cloud accurate to three millimeters. They then produced a 3D, color-coded model of the structure, naming every single beam and matching the position of each to the point cloud. Through this exercise, they identified 140 roof beams that need some level of attention, be it painting or full replacement. They also discovered signs of deformation––an unwelcome surprise.
“Since we can analyze each 360-degree scan as soon as the X7 has captured it, we could not only see that the structure was not built according to the original design plans, we could see that the structure wasn’t straight,” says Nicieza. “The deformation isn’t extreme but it is an additional issue that will need to be integrated into a refurbishment plan. And the city would never have known about this risk if we hadn’t used laser scanning.”
Nicieza and Alonso presented the point cloud, photos and model to the city council, showing precisely which beams are rusted and where they are, and pointed out the deformation.
“Once they saw a 3D model of exactly how much damage there is in just one section, they understood how this information could help them develop a specific refurbishment plan based on only what needs to be repaired,” says Nicieza. “That’s very valuable.”
Based on the helpful information, the council is planning to develop a “digital twin” of the stadium, which will require a precise as-built 3D model. Having proven the precision, speed and cost value of laser scanning, Simetría is waiting to “suit up” for the survey game.