Building a road is no easy task. It involves a lot of complex engineering and precision work. Every stage of the construction—from clearing and excavation to fine grading and paving—requires careful planning and attention to detail.
Luckily, drones are making the process a lot easier. They provide geographic information system (GIS) data on the road that civil engineers and construction crews can rely on to make more strategic decisions.
Unmanned aerial vehicles (UAVs) can survey and measure the earth’s foundation, help direct the pouring of asphalt and concrete, and provide detailed visual insight throughout the project.
So if you haven’t considered using drones in road and highway construction before, here are the top 5 benefits you can look forward to:
Table of Contents
1. Accurate & Detailed Data
For one, drones are a powerful tool for assessing the soil before road construction begins. For example, they can perform accurate land surveys with sub-centimeter level accuracy and give you the slope between any two points. This helps you know where you can pave and what obstacles to avoid.
Here are many of the different survey data types you can expect:
- Topographic maps—A topographic map is a detailed aerial map that shows changes in elevation. Drones generate these with the help of LiDAR lasers. LiDAR stands for light detection and ranging and involves measuring the time it takes pulsing laser beams to travel from the aircraft to the earth and back again. It’s like sonar but in the air. This allows you to measure exact distances like elevation at sub-centimeter level accuracy and even see through obstacles like trees. Such topographic maps help you know the location of valleys, peaks, and ridges when planning road routes.
- Orthomosaic maps—For larger areas, drones can collect thousands of aerial photos that can be stitched together into an orthomosaic map for a much more detailed level of baseline data. Geometrically corrected for lens tilt and camera distortion, orthomosaic images can give you map resolutions of up to 0.7 inches per pixel! This gives stakeholders a comprehensive view of the road to track construction progress.
What's included in YOUR GUIDE...
A Proven Roadmap of Success for Implementing Drones in Construction.
A List of Red Flags to Avoid When Hiring Drone Service Providers.
How to Persuade Your Leadership Team to Leverage Drones on Every Jobsite.
- Corridor maps—A corridor map is a linear 2D or 3D plan of a road. Typically, they are generated by drones equipped with real-time kinematic (RTK) positioning technology, which matches geotagged images with GPS data sent from a ground base to ensure centimeter-level geographical accuracy. Corridor maps help road developers, electrical companies, and oil and gas operators better manage encroaching vegetation and right of way permits.
- Earthwork surveys—Drone earthwork surveys measure the soil on a construction site within 1 to 2% of true volume. They can include cut and fill reports, stockpile measurements, and more so you know how much earth to import and export offsite and when to replenish materials. But they also help you know what vegetation, debris, or other obstructions to clear, and where a road will need to include a bridge or tunnel to circumnavigate natural land obstacles.
Before any asphalt paving begins, drone earthwork surveys can make sure the earth’s surface complies with building plans. And they can even help you plan the most efficient haul routes for moving materials. Drones do this with the help of RTK technology and sometimes ground control points (GCPs), which are physical markers spread across the construction site to help position the drone.
2. Improved Decision Making
Drone data helps improve on-the-ground decision-making. For example, UAVs can hover above the construction site to monitor supply levels and the status of equipment. That way, project managers know when to reallocate materials, report damages or accidents, and adjust plans to get back on schedule.
Drone footage can also be viewed in real-time through a live feed. This allows multiple workers to view the screen at once to check on construction progress and make more tactical and quick decisions on site. For example, a quick drone flight can detect a mistake in the mounting or fine grading of the soil so that workers can fix it before they move on. Or the drone data can be processed with drone software within hours for teams to review later.
Drone documentation can also protect you on the legal front. For example, if somebody claims they were injured due to poor site safety conditions, you can review the drone footage for the day in question to see what hazards were present. If the case went before a court, you’d have valuable evidence on your side.
All these drone applications help you avoid making costly mistakes. After all, the tiniest miscalculation spread across miles of road can turn into a big problem. So use drone data to get it right the first time and avoid the need to backtrack.
3. Faster Data Collection
Of course, one of the main benefits of using drones in road construction is their speed. To send an engineer on foot to collect the same data with a handheld camera can be an incredibly slow process. Drones can cover large stretches of road and they can capture far more data from various angles.
“We were flying a road project- about 8,500 feet of road, with 400 feet on either side of the center line. We were actually able to complete that project in 2 days compared to what it took conventionally, which was 12 weeks.”
- Ross Kenney, NEI UAS Sales and Support Lead
Another reason drones can collect data faster is that they are not slowed down by on-the-ground hazards. Site material, equipment, and traffic can get in the way when you’re on foot. But not with drones. They can map entire road corridors from the air without a problem.
In the end, road construction surveys that used to take several weeks can now be done in a matter of days with drones. And drones can give you more frequent reports while staying incredibly cost- and time-efficient.
4. Visual Documentation
UAVs also provide better visual documentation of each layer of the road as it is laid. These include the following:
- The surface course (75-150 mm)—This is the top layer that comes in contact with vehicles. Sometimes it’s divided into the wearing course (25-50 mm) and the binder course (10-100 mm). And it’s usually made of hot mix asphalt (HMA).
- The base course (100-300 mm)—This is the layer directly beneath the surface course. It provides additional support and distribution and helps with drainage. It’s also usually made out of HMA or crushed aggregate.
- The subbase course (100-300 mm)—This layer beneath the base course provides additional load distribution and helps with drainage as well. It’s usually made of HMA or crushed aggregate.
- The subgrade (150-300 mm)—This is the deepest layer of the road. It’s made of compacted soil and serves as the foundation for the other pavement layers.
Together, these layers act as a stable surface for the final road. But capturing aerial drone footage of each one before moving on to the next allows you to keep a detailed visual progress record as you go.
Here are the two main ways drones can capture the road layers:
- By using LIDAR and photogrammetry technology to generate 3D point clouds in the form of digital surface models (DSMs) and digital terrain models (DTMs)
- By stitching together several RGB shots to create large orthomosaic maps
Either type of visual documentation allows you to bring your construction model to life so you can better manage the project from start to finish.
5. Improved Worker and Site Safety
Lastly, drones increase worker and site safety. Since drones capture data from the air, you don’t need to impose unnecessary risk on workers when inspecting the road in or near moving traffic. Plus, drones’ bird’s eye view can help you anticipate and prevent dangerous situations before they happen. All in all, this leads to fewer worker accidents, less liability, and lower insurance premiums.
For example, after a New Jersey retaining wall collapsed in March 2021, drones were able to quickly fly over the site to help crews determine the severity of the damage while the pilot was located a safe distance from the hazard area.
Drones can also fly at all hours of the day and night to monitor the construction site when work is paused. If there is any suspicious activity, drones can send an alert to management to help prevent vandalism or equipment theft. Overall, drones lower worker and site safety issues to a much more manageable level.
Next Steps: Getting Started with Drones for Road Construction
Now that you know the top benefits of using drones in road and highway construction, you might wonder how you can implement them in your next construction project.
Well, The Drone Life is here to help. Our team of expert drone pilots has years of experience working on all types of infrastructure projects. And we can help you with yours, too! Whether you need land surveys, progress monitoring, or detailed inspections, we’ll help you take your next road construction project to the next level. Feel free to contact us today for a free consultation.
What's included in YOUR GUIDE...
A Proven Roadmap of Success for Implementing Drones in Construction.
A List of Red Flags to Avoid When Hiring Drone Service Providers.
How to Persuade Your Leadership Team to Leverage Drones on Every Jobsite.
