BY DEBRA WOOD
Technology continues evolving, offering opportunities for construction firms to automate some practices and explore new ways to build. Drones have made significant inroads, while robotics and 3D printing hold potential but are not in widespread use.
“A lot of things make the construction industry challenging, so you have to be smart and use technology tools,” says Raynald Morris, chief information officer at W. M. Jordan Co. of Newport News, Virginia, a member of AGC of Virginia, Carolinas AGC and the AGC IT Steering Committee. “Construction has been slow to adopt technology, but during the past five years it has grown substantially as has understanding of how technology can benefit us.”
Small and large contractors are deploying drones, unmanned aerial systems [UAS], for aerial photography, surveying, data collection and more. Some have established their own fleets. Others hire drone pilots to handle the flights, and some follow a hybrid method.
“This is a brand new technology for our industry, and we are learning as we go,” says Chip Reid, CEO of Current Builders of Pompano Beach, Florida, a member of South Florida Chapter-AGC. “It’s exciting what the potential is.”
Nathan Wood, chief enabling officer of the consulting firm SpectrumAEC of San Francisco, suggests contractors assess how they plan to use the drone, who can fly it, and how often they will use it before purchasing one.
“You would need to be doing quite a bit of work to bring in house,” Wood says. “More and more companies are outsourcing, because it is easier.”
Bob Etris, a partner and director with Evans, an aviation-consulting firm in Falls Church, Virginia, callsthis a fast-evolving hardware and technology market, with drones continually improving.
W. M. Jordan started using drones four years ago initially for photography but has since expanded to use them for marketing, site logistics planning, land surveying, monitoring progress, thermal imaging, measuring the amount of dirt or gravel moved and inspecting existing facilities. The company’s drones can carry many different types of sensors.
“That’s just stuff you can do today; down the road, who knows,” Morris says.
A drone’s thermal imaging scan of an existing building showed heat loss through single-pane glass windows on one side of the building but not on the side with the double-pane glass. After Jordan replaced the windows, a second flyover showed no heat loss.
“When you have the images side by side, you can see it clearly,” Morris said. “We are doing more with the thermal piece, because it brings a lot of value.”
The company recently used a drone to capture images of a brick fireplace on a hotel building being restored. In the past, the company would have installed scaffolding to assess the condition. In three hours, Jordan had images and could determine the level of work needed to be performed.
Current began using drones after a client introduced it to the technology on a large student dorm project in Boca Raton, Florida. It uses the unmanned aircraft for tracking logistics, how materials flow onto the site; assessing areas inaccessible by foot; or observing areas that could be a potential safety risk.
“When you see a site from a drone, it gives you a different perspective than a 2D plan,” Reid says. “It provides more information to our team.”
Reid adds that Current Builders is investigating laser scanning from a drone. He encouraged the industry to collaborate about best practices for the use of drones.
Assessments of inaccessible sites are a natural candidate for drones. A surveying customer of 3D Robotics, based in Berkeley, California, used a drone to survey a site with quick sinking mud, which would have been next to impossible using traditional survey methods. 3D Robotics provides drones and software for the construction industry.
Brasfield & Gorrie, headquartered in Birmingham, Alabama, a member of multiple AGC chapters, recently scanned an existing railroad span that the company will be replacing in a remote marsh that is only accessible by boat.
“Using drones to scan the span allowed the project team to have a perfect representation of the site from the office hundreds of miles away,” says Hunter Cole, virtual design coordinator for Brasfield & Gorrie. “This data will be extremely valuable to the project team leaders, particularly when they need measurements that would traditionally require hours of travel by car and boat.”
Brasfield & Gorrie began experimenting with drones on jobsites several years ago.
“Since that time, the technology and the FAA regulations have evolved enough to allow us to achieve greater value from these systems,” Cole says.
Brasfield & Gorrie has used drones to assess site work progress too. When appropriate, such as when hazardous conditions are present, its safety teams use drone-generated 3D models to conduct safety assessments in virtual reality—sometimes hundreds of miles away from the project—and often identify avoidable risks.
“With these capabilities, [project members] across the country can have a high level of awareness of a remote jobsite,” Cole explains. “They can, in real-time, understand the changing site, take measurements of conditions on site, view the jobsite in 3D, take advanced measurements, overlay design drawings and documents to confirm quality control and more.”
Tim Eichelberger, chief pilot for Brasfield & Gorrie, explains that drones take 2D images, and drone software generates 3D models using a processing technique called photogrammetry, which stiches those photos into a highly accurate 3D model. .
“We can compare a 3D point cloud of a structure to the engineer’s design model to confirm accuracy,” Eichelberger says. “It has quickly become a part of our process.”
In addition to surveying, 3D Robotics drones can collect data to perform a cut-and-fill analysis. Hugh McFall, marketing specialist at 3D Robotics, reports that Bogh Engineering of Beaumont, California, a member of AGC of California, is using drones for this purpose at 14 different jobsites weekly.
“Bogh Engineering is flying its jobsites almost daily, capturing volume data and reporting progress to owners and other stakeholders,” McFall explains. Management can quickly become aware of and address any issues.
Wood reports that a client of his noted a large amount of dirt went missing. The contractor could see on the drone images which truck took the dirt, read the name on the side of the vehicle and took action.
“It’s nice to have the data to go back,” Wood says.
The FAA has issued rules for unmanned aerial vehicles, drones—Title 14 of the Code of Federal Regulation Part 107. Before flying a drone, it must be registered with the FAA if the drone is more than 0.55 pounds and less than 55 pounds. The operator must hold a remote pilot airman certificate and pass Transportation Security Administration vetting. The aircraft must be kept in site, fly under 400 feet, fly during the day, fly at or below 100 mph, yield the right of way to manned aircraft, not fly above people and not fly from a moving vehicle. Contractors can apply for waivers to some requirements.
“A potential drone pilot with no previous aviation experience can now study for a few weeks and take an exam that tests knowledge of the FAA UAS regulations, aircraft performance, weather theory, airspace interpretation, etc.,” Cole says. “Upon passing the exam, individuals can submit an application with the FAA to earn the FAA Remote Pilot certificate.”
Brasfield & Gorrie now has 17 personnel who have completed the process, including field engineers and project managers. The company has developed its own training materials, in addition to FAA requirements, to ensure it operates drones in the safest manner possible. Cole advises others to follow the rules closely, take advantage of training opportunities and spend as much time on developing a corporate policy as flying.
“The drone space is moving so fast that it is critical to keep your operations agile and not get bogged down in the particulars of any tool,” Cole says.
On June 21, 2016, the Federal Aviation Administration (FAA) finalized a new and comprehensive set of rules for the commercial use of small drones in all industries, including construction. This action completes a rulemaking process that the FAA began in February of 2015—in an effort to meet Congressional demands and to stem a rapidly rising tide of applications for individual exemptions from longstanding rules that make no distinction between manned and unmanned aircraft. Through Jan. 20, 2016, the FAA had granted 3,136 of these exemptions for the commercial use of drones, and significantly, 48 percent of that total were for uses in the construction and engineering.
AGC submitted detailed comments on the proposed rules and continues to assess the FAA’s response. At the outset of its letter to the agency, AGC encouraged the FAA “to create a straightforward and streamlined process for companies to request exemptions from the agency’s [proposed] requirements and restrictions” where alternative approaches to “specific aircraft operations” would be “equally effective” in addressing the agency’s concerns.
Perhaps the best news is that the FAA has taken that advice, adding “waiver authority to the regulatory text in order to accommodate . . . unique operational circumstances.” The agency has created a new “certificate-of-waiver process” specifically to give the agency the flexibility “to assess case-specific information concerning a small UAS operation that takes place in a unique operating environment,” such as a construction jobsite.
Morris says he thinks new FAA rules have helped the construction industry. He has the remote pilot certificate, and Jordan maintains flight manuals and other documentation to support drone operations. On occasion, the company will bring in a third-party to complete any high-risk drone operations.
If a firm is considering a drone program, Morris suggests trying it with an inexpensive drone and learning how to fly it oneself. Then if the operator feels comfortable, the company can make a more serious investment in a commercial drone.
“We have taken a slow and steady approach, always following the established FAA guidelines and recommendations,” Morris says.
Etris recommends companies develop a plan for the drone’s use and measure the drone’s performance and value. He also advised creating policies and evaluating the costs and benefits before moving forward to ensure a drone and personnel are used wisely. Additionally, external expertise is available to help firms understand the requirements and best practices in the use of drones.
Robots can perform certain tasks better than humans, and successful businesses like their bottom line. Robotic total stations have become an industry standard for building layout. Morris calls the total robotic station’s accuracy “incredible.”
New developments allow for robotic brick laying, painting and pipe crawling. Morris foresees the day when robotics will paint buildings or lay flooring when other trades leave for the day.
W. G. Yates & Sons Construction Co. of Philadelphia, Mississippi, a member of multiple AGC chapters and the AGC IT Steering Committee, piloted the SAM100, a semi-automated mason from Construction Robotics in Victor, New York. The manufacturer reports it can build walls six times faster than a human bricklayer.
“We learned a lot,” says Benjamin Crosby, director of BIM and virtual design and construction at Yates. “We wanted to know what it takes to implement and use the robotic brick mason.”
Crosby indicates the company met that objective. He found the machine worked best on long runs and not on short distances. It requires special scaffolding, which added to the expense of the pilot. Crosby says he thinks Yates would use it again, if it had a project with a significant amount of brickwork.
SAM follows a model uploaded to a tablet attached to the robot. The machine can set the bricks in different designs, including company logos. Every brick has a number. The robotic arm grabs a brick, places mortar on it and sets it in place. It measures the distance from the prior brick and knows where to place it. The robot records every brick, the slurry of the grout mix and other data.
“The quality of the work where the robot ran was superb,” Crosby says. “Every brick was online. The masons did not have to come back and redo things.”
Robots do not necessarily replace people, yet working with them requires different skills, Morris says. He suggested trade people may need retraining to maintain the robotic equipment. For instance, people still need to program the robots. In the case of SAM100, the foreman follows behind to remove excess grout and tool joints. SAM also cannot lay the last brick in the line of bricks.
“The masons I talked to liked it,” Crosby says. “We were changing their work structure. They thought it was taking away the monotonous work, but they still had plenty of work to do…. Overall, there were not jobs lost. We see it as an opportunity.”
3D concrete printing has been slower to take off in the United States, although contractors have used it in other countries. Many AGC members have investigated the technology but have not taken the lead to let concrete printers build their buildings.
“The larger-scale stuff is not there yet,” Morris says. “But on a smaller scale, there are components to buildings that could be 3D printed.”
Additionally, models and prototypes could be 3D printed. The idea, Morris says, would be for issues to get worked out before construction takes place in the field.
Crosby has investigated 3D concrete printing. He thinks building codes in the U.S. may be holding back 3D printing as a building method in this country. In other countries, the concrete 3D printer places layer upon layer of concrete, according to an uploaded model.
“The printer part is easy; the challenge is the mix and the fiber content, so it adheres layer to layer,” Crosby says. Another issue involves cleaning the concrete out of the printer and lines.
Despite those challenges, Cole thinks “3D printing has great potential for concrete structures and steel erection. It’s just a matter of time before the technology scales in size to allow this to take off.”