Constru-Tech

Creating the Physical World, Digitally

Advances in the way work is viewed are transforming the construction industry

By KYLE BACKER

Chris Brown Boe Evanson

Technology is changing how we live and work at a rapidly increasing rate. From smartphones and smart home systems to entertainment and gaming options, new innovations are being introduced daily. Even the construction industry, which has a reputation for being traditional and resistant to change, is embracing hightech advances that can help deliver projects on time with less labor and in a safer manner.

“What I’ve noticed over the last five years is that tech companies are addressing construction problems. We’re seeing a lot more software and products that are very userfriendly. They’re not built just around a person who has 20 or 30 years of experience,” says Chris Brown, director of preconstruction and advanced technology for Willmeng Construction.

That’s not to say that folks in the construction industry are Luddites. Building information technology, or BIM, has been used for more than a decade to create 3D renderings of what used to be confined to 2D technical drawings. Now, however, new products are improving on older technology and leveraging it in novel ways.

ADDING VALUE

Ken Smerz is the CEO of Zelus, a firm that specializes in BIM and virtual design and construction (VDC). During his time as a licensed contractor in California, he learned the value of precise measurements — and that nothing is built exactly to its intended design. To help create an accurate picture of already-built environments, Zelus uses lidar scanning to create a digital representation of reality.

“We use lidar scanners on tripods or drones to shoot out about 1 million points of light per second. Whenever the laser touches something, its light bounces off that surface and back into the scanner,” Smerz explains. “It’s the same technology that police officers use to see if you’re driving too fast, but it’s just recently been used in the construction field.”

Having accurate measurements in the form of a BIM model is crucial when installing prefabricated elements and provides a common template that allows the various trades to coordinate their work.

“Prefabrication seems like it would be easy. You build what’s shown in the model, you take the item into the field, and theoretically you just bolt it in place,” Brown says. “But if one trade installs a sprinkler pipe in a place that it wasn’t supposed to be, that prefabricated piece may not work anymore. So now you’ve got to cut it apart and change it out in the field.”

Less rework has a positive effect on project timelines and budgets.

“Reports by the National Institute of Standards and Technology show that 13% of all project costs on new builds are from rework. Using 3D technology, we can spot where an electrical conduit might clash with the mechanical systems to help reduce rework and compress schedules,” Smerz says.

Similar technology can help track the progress on a job site. Scott Root, executive director of strategy and innovation for Kitchell Contractors, uses a software program called OpenSpace to create a visual representation of the job site using 360-degree cameras. The program uses artificial intelligence (AI) to assign percentage-complete values to the pictures, so subsequent captures can show how much progress has been made since the last capture.

“During the pandemic, we didn’t have our design partners or owners on the job site as often as they normally are. But OpenSpace pushed information to them in real time so they could look at any day and see the progress,” Root notes. “On our side, we can use the AI aspects to understand, for example, when the drywall is going in and what percentage is already in, which falls right into our construction management plans.”

Scott Root Ken Smerz

BUILDING INFORMATION TECHNOLOGY:

3D BIM renderings give builders detailed insight into all components of a project.

NEW WAYS OF SEEING

Virtual reality (VR) has also entered the construction field. Wearing a VR headset allows employees and clients to interact with a 3D model and gain a better feel for the spatial relation of the elements before a single shovel hits the dirt.

“In a traditional design phase, clients see several different iterations of a project. If we can bring it into VR and have them go through iterations in real time, we can get decisions solidified faster,” Root says.

Virtual reality also allows the people who ultimately will be working in a space to influence the design. For example, during the design of a hospital room, medical professionals can use VR to provide feedback on everything from the flow of the room to the placement of electrical outlets.

“They’re not builders or designers, but if you can make them feel as though they’re doing their job within a VR setting and using their expertise to experience how a space works, I think that’s where we get the most value out of these tools,” Root says.

Because VR headsets cover the wearer’s field of vision to create an immersive experience, they currently aren’t used in the field. Augmented reality (AR) headsets, however, are closer in size to glasses and provide a digital overlay on what the user is seeing in real time.

Boe Evanson, senior project manager at Weitz, used Microsoft’s HoloLens AR headsets and a software called VisualLive to utilize BIM models in the field during the recent expansion of Sagewood, a senior living facility in North Phoenix. The facility’s underground parking garage had a 14-inch-thick post tension slab with thousands of tension cables running through it, with little room for error on the penetrations coming through the slab.

“We used the HoloLens AR headsets to walk the deck before we poured. We were able to see our pipe penetrations coming up through the deck, then, through the HoloLens, see the projected hologram of the walls to make sure those pipes were falling in the walls like they were supposed to,” Evanson recalls. “We caught several items and were able to resolve them before we poured that slab, which otherwise could have been an issue for us.”

First of its Kind

Two projects bring new construction techniques to Arizona

By KYLE BACKER

The construction industry has a rich history of developing methods to make the work of erecting buildings safer, more efficient and better for the environment. Two new projects currently underway in the Valley showcase some innovative and eco-friendly materials that are being used for the first time in Arizona.

ADVANCED CONCRETE DESIGN

Located at the southwest corner of University Drive and Rural Road in Tempe, Arizona State University’s Interdisciplinary Science and Technology 7 (ISTB-7) building is a 281,000-gross-square-foot facility that will house multiple sustainability-focused educational and research programs.

Because the project was designed to meet specifications for LEED Gold at a minimum, McCarthy Building Companies used a new technique known as BubbleDeck to reduce the amount of concrete required.

Carlos Diaz, senior project director for McCarthy, says that the aggressive sustainability goals for the project led McCarthy to use BubbleDeck’s void form slab system. Rebar cages hold 13-inch hollow spheres, made from recycled plastic, that displace concrete as it is poured, creating air-filled voids within the deck. Using this system requires the builder to slightly alter the process of how a slab is typically made.

“You can’t just place the spheres in the rebar and pour the deck all the way to finished elevation, because the spheres will want to float up,” Diaz explains. “Initially, you have to pour about one-third of your total deck thickness. That’s just enough to lock the cage to the form and prevent that floating effect. Then you come back 10 to 24 hours later, and you pour the second lift.”

The lighter concrete also reduce foundation load requirements. “With traditional concrete slabs, column spacing at 20 feet is typical. By removing all that weight that would want to sag in the middle, we have columns spaced at 37 feet, which makes the area feel more open like a warehouse,” Diaz continues.

Because concrete has a large carbon footprint, reducing the amount used on a project has knock-on effects. “Using 1,000 less cubic yards of concrete means there’s 100 less trucks that we have to coordinate and bring onto the job site and 100 less trucks driving on the road. We also don’t need to operate a large piece of equipment to pump all that concrete,” Diaz says.

BUBBLEDECK: Team members from McCarthy Building Companies install the hollow sphere-and-rebar BubbleDeck system at ASU’s ISTB-7 building.

Carlos Diaz George Foristall

With sustainability being a top priority for the stakeholders, components were stretched in other ways. McCarthy used a concrete mix with 40% fly ash, a byproduct harvested from coal-burning facilities by attaching nets to the top of exhaust fans.

“Using that much fly ash is tough to do. The concrete gains strength slower, so it’s a bit of a burden on the project schedule,” Diaz remarks. “Applying it to the entire project — 18,000 cubic yards of concrete — was a big sustainability milestone for us.”

THE FUTURE OF WOOD

Visually, the five-story, 184,000-square-foot office building in downtown Tempe stands out thanks to its sleek design that features a mix of wood, concrete, steel and glass. But The Beam on Farmer also attracts attention due to its use of cross laminated timber (CLT). “There are only a handful of office buildings in the U.S. that have this to date, but this technology has been used for over 20 years in Europe,” says George Foristall, director of real estate development at Mortenson Construction.

Cross laminated timber uses 1-by6-inch boards that are stacked atop each other, with each layer turned 90 degrees from the previous one to increase structural rigidity. The wood comes from young trees, which helps with the project’s ecological impact. “If you use new-growth trees, they grow fast and you’re not cutting down a 100-year-old tree. As new trees grow and you use them to make CLT, you capture the carbon within the fibers of the project,” Foristall says.

The CLT is prefabricated and shipped to the job site, meaning there’s no waste created from cutting after delivery. “Production is nearly, if not totally, zero waste. Every piece gets cut and utilized into another piece, all the way through the lifecycle and down to the sawdust that gets put into oriented strand board, or OSB,” Forestall notes. The timber also reduces the use of carbonintensive materials. “Concrete is one of the most environmentally unfriendly products to generate. By using CLT, we’re reducing the amount of concrete needed significantly,” he adds.

To showcase the CLT inside the building, an underfloor air distribution (UFAD) system was used, which eliminates the need for overhead ductwork. The system also helps with the air quality. “With the underfloor air distribution system, the cold air comes from the bottom of the floor and then naturally rises to the ceiling return as it heats up. The air is only moving in one direction, so you don’t cross contaminate the old air and the new air within the space,” Foristall explains. “All the filters in the world aren’t going to help clean the air that’s selfcontaminated before it gets to you.”

CROSS LAMINATED TIMBER: Environmentally friendly and sustainable, CLT will be on full display for the first time in Arizona in The Beam on Farmer.