Is it illusion or reality? A surveyor knows.
Blog by Emily Pierce, PLS, CFedS, and Bob Beilfuss, PLS
I was chatting the other day with a colleague from my surveying days, Bob Beilfuss, a surveyor from Germantown, Wisconsin. Since I’m now working for Berntsen, Bob shared some of his favorite stories about the Berntsen products he uses. It was an interesting and informative chat, so I asked him to share his stories with you.
First, a few words about Bob. He is also a former President of the Wisconsin Society of Land Surveyors (WSLS). Bob has been a surveyor for residential and commercial markets for more than 40 years, and we’ve served on the WSLS Board of Directors together, as well as participated in the National Society of Professional Surveyors (NSPS) activities together as well. He and I both enjoyed traveling to the Texas Society of Professional Surveyors fall conference with the NSPS Board three years ago.
Bob has developed considerable expertise in using Rothbucher targets for monitoring surveys. They’re the only targets he uses because they are durable, the center point is well defined, making it easy to see at a wide range of distances, and they are surveyor field-tested.
Reality or Illusion - How Rothbucher Smart Targets Helped Me Find the Truth
“I used Rothbucher targets on two retaining wall monitoring surveys here in Germantown, WI.
Is it leaning or does it just look that way?
The first survey involved monitoring a six foot retaining wall located between a new roadway and a wetland area. The highway department staff believed the wall had begun pitching away from the road toward the wetland. Additionally, cracks in the ground on the backside of the curb had appeared, lending credence to this theory.
My team bought eight RSAK80 targets from Berntsen and glued them to the top wall cap of the retaining wall.
Then, I established a 3-point control network that was visible to the wall points and was based on a couple of intervisible boundary corners that were monumented with 1" iron pipe with plastic caps.
We also established chiseled crosses in the concrete curb head opposite each Rothbucher target.
We used a Trimble S6 robot to take all of the control and target measurements to the targets and the chiseled crosses. The measurements to the crosses were taken using a standard prism and rover rod pair with the rod stabilized with a bipod.
After the initial measurements were taken to all the targets and crosses, we set up a monitoring schedule. We completed a round of measurements every day for a week, then followed up with a single round of measurements every other week for two months.
The survey data was clear. All of the monitoring measurements detected NO movement between the control network between the targets and the crosses.
Rothbucher RSAK 80 Smart Targets glued to the top of the retaining wall.
The wall was not moving – the leaning was merely an illusion because the wall had been built on a curve and appeared to be leaning but was well-built, safe and sound.”
Our survey provided proof that the wall was safe and posed no risk of failure due to pitch.
Bob uses Berntsen’s Rothbucher targets for his monitoring projects because they are easy to use, accurate, adaptable and highly precise.
Bob’s project is quite similar to a lot of surveying and monitoring projects that many surveyors frequently face. We’re so happy at Berntsen to be offering the Rothbucher family of reflective targets, prisms and adapters.
We have a wide range available to fit all your needs. Our reflective target tape is perfect for a quick and easy solution.
The RSMP280 prism with the RSFP-X80 Adapter
But, if you require something a bit more permanent, we offer targets designed to be visible at multiple angles, and even some that swivel. Additionally, our Rothbucher line includes a full range of prisms, such as the RSMP280s and 380s that can be mounted to universal mounting plate (RSFP-x80 shown at the left) that provides a resumption point.
Surveyors care about precision and accuracy, and that’s why they carefully select the best total stations. It makes sense to also invest in field-tested targets, prisms, and reflectors that adhere to the highest standards of quality, precision, and practicality – Rothbucher from Berntsen.
Over the next few months, I’ll be sharing “how-to” content about Berntsen’s Rothbucher product line. These tools can help you expand your business by including monitoring projects, surveys that require drones and ways you can offer value-adds for construction
If you have questions about Rothbucher products, we have answers. Just send us a note through email@berntsen.com.