Efficiently Surveying an Entire Stadium

Posted: 7/27/2016

Never properly documented

After fans had to say goodbye to their former stadium Alkmaarderhout with a heavy heart, the brand-new stadium was officially opened with a friendly match against Arsenal in 2006. But in the midst of the celebrations of this new beginning, it turned out the building was not entirely ready for its duty.

"When the AZ stadium was built, the financial crisis was demanding attention. As a result, the state the building was in at the time it was opened, was never properly documented," says Collin van Kooten, BIM consultant with CAD & Company.

Because of this lack of documentation, it was difficult to get a clear view of the stadium's maintenance needs. CAD & Company was asked to assist AZ in analyzing the upkeep situation, ultimately making it easier to plan the work that needs to be done and to effectively direct the maintenance staff.

A cloud of positions
"Of course there were models of how it was supposed to be built, but there are no documents that tell us the stadium was indeed completed that way. That's why the question was: what's the current situation? We've mapped it by making a point cloud," says Collin.

CAD & Company created this point cloud by using data collection and mapping devices. Basically, a point cloud is a visual representation of each measured point in space. All of these points have their own X, Y, and Z coordinates, together forming a 3D image. Thus, it provides insights into every brick, bolt and bucket seat in the stadium.

"The point cloud can now be put to use in multiple ways. We can turn it into a virtual model, a BIM model of the building. Currently, AZ's priority is with the construction of a new training complex, in which they get to know the possibilities of such a model. So right now, it's an 'as-is'. We could make it available in different applications."

Two or three millimeters

Among those applications is one called BIM 360 Field. As Van Kooten says, it 'takes BIM to the building site'. And it is a valuable tool. "It makes it easier for technical managers and maintenance staff to make notes while walking through the stadium with their iPads, and quickly report what needs to be done. For example, if a door is crooked or there is water somewhere it isn't supposed to be, they can take a picture and immediately pass it on to the person who is responsible for it."

"The drawings that were already available can be found in the application, and the point cloud will also be made available there. Then you can use it as you walk through the stadium, to compare the information from the point cloud with the current situation. If it turns out there is maintenance to be done, you can use the point cloud as a great point of reference."

"The point cloud is very precise. There might be a deviation of two, three millimeters for every ten meters. In the case of such a large building as the AZ stadium, a three millimeter deviation is no problem at all.

A real time saver
"Before it was possible to make such a point cloud, the surveying had to be done manually, by multiple employees. Well, here you have this huge, oval-shaped structure - good luck drawing diagonals and measuring that."

Before moving on to being a BIM consultant, Van Kooten used to be an architect. "When we were commissioned to renovate buildings, we did a lot of manual surveying. Sometimes you had to go back three or four times because it turned out you had not taken a look at each and every nook and cranny, or you didn't get all the sizes right. Nowadays, we have software that takes care of all of it."

"You save a lot of time. How much? That varies, depending on the building you have to survey. The AZ stadium was surveyed adequately in just two days. If we had to do that by hand... Let's just say, it's a huge difference."

CAD & Company works with several kinds of software, including Topcon's [internal link]data collection and mapping devices[/internal link], to help companies like AZ enhance the transparency and effectiveness of their maintenance work. "We work with software from different suppliers, and what's great is that these programs interact more and more seamlessly. It is becoming very easy to conduct a scan, load all the information into our applications and put that to practical use."