As any surveyor knows, when it comes to installing survey targets, not all surfaces are created equal. Ironically enough, many of the structures that require the most frequent monitoring are also the ones where targets and prisms are most difficult to place.
To solve this challenge, German manufacturer Rothbucher Systeme set out to build a series of survey targets that could go where other targets couldn’t while retaining the same level of precision. The result was the Smart Angle Target––a 90º-angled control monument whose lightweight and versatile construction allows it go just about anywhere.
While they’ve been used extensively in high-profile projects like the brand new World Trade Center Transportation Hub, these targets are also helping surveyors overcome local project challenges in areas all over the world.
We’ve highlighted four real-world surveying applications for Smart Angle Targets below.
One of the most common and most difficult surfaces seen on building sites, facades can present major challenges to surveyors dealing with unique angles, sharp corners and high public visibility.
Smart Angled Targets’ small size, 90º angle, and ability to be glued to a surface, make it the perfect choice to deploy in just about any facade layout using a simple process:
Fix and number survey targets at each floor level of the facade at 3-meter intervals at all corners. Measure the coordinates and record the data.
Bridges present their own set of challenges. Perhaps most common is the issue of installation. Concrete and steel can make drilling a nightmare if not completely impossible. When traditional targets can be placed, exposure to water and high winds can lead to costly delays when targets degrade.
For long-term monitoring of bridges, the installation process is simple:
Use a stamping set and waterproof pen to indicate the position numbers or sequential numbers on the survey targets and attach them at the following places:
● All piers of the bridge at low level, center level and top level of the piers
● Above and below all bridge supports
● On the bridge caps. Screw RSAMG80 type adapters into the existing anchor sleeves at 5 meters spacings using 2-component adhesive. Align according to the surveyor’s instructions.
Where there are no anchor sleeves, use adapters of the RSAM80 or RSAK80 type for fixing, aligning them to the fixed point and carry out control measurements as requested by the authority in charge.
Railroads present an array of challenges for survey teams due to the difficult terrain and less-than-ideal conditions for proper target placement on railroad tracks.
Along with bridges, buildings, and other structures where periodic monitoring is essential to ensuring safety and long-term reliability, railroads often require relatively frequent upkeep due to the strains and pressures constantly being exerted on them.
Once a Smart Angle Target is attached to a track, these targets make it possible to forgo scheduling around the railroad’s timetable by allowing crews to make their measurements outside of the danger zone and out of the path of trains. This also provides a benefit to survey crews themselves as personnel can conduct their work without worrying about entering a hazard zone to conduct routine work.
Use the following guidelines for proper installation:
First, clean the fixing places on the track. Next, install the RSAK130 or RSMP180 plastic adapter by first numbering the adapters and then attaching them with mounting adhesive RSMK-fix at approx. 3-meter intervals.
The zero point measurement can be carried out on the following day. For free positioning, attach adapters RSAK80g to adjoining masts and measure their positions.
Much like bridges, tunnels require both temporary monitoring during construction and long-term monitoring afterward. Angled Smart Targets give surveyors the ability to attach targets to virtually any surface while getting incredibly precise measurements even at long distances.
For tunnel construction, the process is straightforward:
Attach several survey targets on a firm substrate and measure and record their position to allow easy on-site positioning with the tachymeter or total station.
Before fitting, use a stamping set to mark a position or sequential number on the survey target and then identify it with a waterproof pen. If the targets are placed at axis positions, the elevation and axis designation should also be indicated on the target as described above.
Taking the next step
For survey teams ready to tackle the logistical headaches and technical problems that come with working in difficult areas, Berntsen is proud to provide an array of survey targets and prisms designed especially for these situations.
Click here to view our selection of Rochbucher Systeme Smart Angle Targets, Datums and Reflectors, or request a catalog.