Quick answer: How are Cut/Fills used on construction sites?
Cut/fill extraction, sometimes called “excavation and embankment,” means moving earth from one location to another with the goal of reaching a particular surface or volume.
Construction teams use cut/fill maps generated from topographical surveys, often performed by drones, to see where they need to add material and where to remove it.
Having accurate cut/fill maps helps construction teams plan earthwork projects, track material inventories, and monitor progress.
The largest use case for drone surveying on construction sites is calculating volumes. For those in the industry who rely on accurate cut and fill calculations, this won’t be surprising.
When you’re calculating cut/fill on your worksite, you know that even small deviations in survey data can snowball into big margins of error. Think about your site’s size. Now think about the implications of bad survey data when applied over your whole site.
Thanks to the state of drone hardware and newer, post-processing workflows, drone surveying is having a moment. Drones are at the point where they can deliver measurements with the same level of accuracy as ground-based methods. (When it comes to things like measuring stockpiles, drones can be even more effective, as aerial images capture angles that you simply cannot get on the ground.)
Critically though, the data you get from drones can be collected more affordably, in less time, and more safely. That means you can get your hands on more frequent cut/fill data—as frequently as you want to fly your drone.
Let’s explore how drones can be used to create highly accurate, highly actionable cut/fill maps, and how to leverage drone data visualization platforms to streamline your earthwork planning and project execution.
The value of doing an earthwork takeoff
Carefully tracking your cut/fill is important for a number of reasons. Material movement is an exhaustive, time-consuming practice. That’s why “moving dirt twice” is something all earthwork contractors are constantly working to avoid.
At the earliest possible opportunity, you should fly your drone to take an initial site survey. This will serve as your earthwork takeoff. When you compare it to your final grade design surface, it illustrates exactly how much material you need to move where.
Once you have this data, project planning becomes infinitely easier. Project managers can determine how much labor, machinery, and time will be required to complete the project to spec and schedule accordingly.
The other resource cut/fill data helps you plan for is the material itself. While it’d be ideal if your cuts and fills equaled out, that’s often not the case. One will inevitably be greater than the other, forcing you to either move material off site or purchase more to bring on site.
Figuring out your material logistics needs early on means you can plan further in advance and operate with greater confidence that you understand the true scope of a project.
Calculating Cut and Fill Volumes for Site Analysis
When it comes to construction, sites can vary widely in their plans and look. To illustrate the benefits of drone surveying in calculating cut/fill quantities, let’s look at a housing development site as it covers many aspects of different construction projects.
For a project like this, adherence to design is a big issue. Specifically, getting those housing plots dug out and leveled according to the linework. For repeated, fine-grained cut/fill work like this, 3D visualizations like those from the Propeller Platform can be more helpful than ever in giving you a bird’s-eye view of your whole site or individual plots.
Of course, you’re also looking to track individual progress and productivity on active areas of the site. With Propeller’s simple tools, you can set up measurements that show you volumes for as many areas as you choose to highlight. On-screen calculators instantly show you the cubes for that region.
If you want to compare to a previous survey or to the linework itself, you can do that two ways. Cross-section view:
These colored lines correspond to each survey or surface you’ve uploaded into Propeller. As you move your mouse along those lines, you also get elevations.
Or in 3D:
Sometimes you want to see that virtual-reality look of 3D. For that you can also view the site with 3D overlays of past surveys or your design to see how things are progressing—get a visual read on how much work’s been done and how much is left to go, all without looking at a single spreadsheet.
Never move someone else’s dirt again
Cut and fill quantities go far beyond simple, important volumes you need to take out or put back in the ground. They also determine how you’re billed for moving earth and contractor work. Sadly, too often on construction sites you can get stuck moving someone else’s dirt because the recordkeeping was sparse or you couldn’t prove or disprove the amount of dirt a contractor said they moved.
Using Propeller in combination with the more frequent surveys drones allow you to get a paper trail with rock-solid quantities you can use to mitigate such claims. Whether that’s moving someone’s dirt or realizing an initial topo gave inaccurate quantities of how much dirt would need to be moved, you can get the objective numbers on your job and not be surprised when you walk on site.
One of our customers ran into just this issue. Lange Land Surveying, a full service land surveying company in Arvada, Colorado, had conventional, GPS, and now drone-mapping and analytics capabilities.
They flew a development for their client Remington Homes. Normally a 25-acre lot would mean three days spent in the field. “With Propeller’s AeroPoints ground control hardware, and drone-mapping and analytics software platform, we’re able to fly the entire site in just half a day, so it’s saving us two and a half days of boots on the ground,” Jon Lange of Lange Land Surveying said.
With the existing 3D surface in Propeller, the LLS team uploaded and compared their data against the design and preliminary development surfaces.
The drone flight captured more dirt on each lot than was originally budgeted by Remington Homes. But with this new data, the builder was able to build the additional dirt movement cost into the price of a home, amounting to a $2,000–$3,000 savings per lot.
All in all, their client recouped roughly $187,000 of savings. “Propeller is helping us with land surveying—we’re able to manage our time more wisely,” Lange said. “We’re saving our clients tons of money and making our investment in Propeller back quickly.”
Cut and fill software helps at every stage of construction
As we’ve seen, calculating cut/fill data accurately means potentially reducing costs, smoothing over future disputes, and getting everyone on the same page. When you need to relate these earthwork calculations, platforms like Propeller have easy-to-use reports in both CSV and PDF. You can also grant your team access to the Platform itself. It’s as easy as sending them a link or an email.
What to learn more about how drones improve cut/fill analysis for construction projects? Check out in our FREE ebook, Using Drones for Cut/Fills in Construction.
OR, if you’re ready to start up your first drone program, let’s talk.
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