Bright yellow CAT excavator with a long hydraulic arm demolishes material inside a circular brick wall, lifting debris as dust rises. A clear blue sky with clouds overlooks the scene.

Construction site at sunset: a long concrete wall under formwork panels, red-and-white striped supports, and scattered materials in the foreground, with hills and trees in the distance.

Construction site with a yellow-orange tripod-mounted surveying instrument on a gravel path. Rebar stakes line the sides, outlining a foundation. In the background are building materials, a partially built wall, and a distant structure under a cloudy sky.

A construction site with a yellow CAT excavator digging near a stone retaining wall, while a worker in a neon jacket sets up a surveying tripod. A ladder leans on the wall; the ground is dirt.

Of intelligent machines and proprietary networks

Precise measurements are the basis of every construction project - today they are supplemented by satellite-controlled machine control systems.

GLS Bau und Montage GmbH is a construction company active in the fields of structural and civil engineering, pipeline, landfill and traffic route construction, steel, pipe and plant construction.

The Perg site in Upper Austria is home to the administration and an in-house surveying department. Here, project manager Jürgen Herb and his colleagues coordinate projects from surveying to visualization, construction and invoicing. He supplies the surveying data to the site managers on site and prepares the data for the satellite-based machine control systems.

To prepare a construction site, the technicians transform the coordinates using the rmGEO calculation software and the GNSS transformation module. Interfaces are used to import and export measurement data from the hardware of various manufacturers in use at GLS. rmNETZ, the network adjustment software from rmDATA, is also used whenever networks are not already supplied by the client.

GNNS construction site systems and i-machines

Jürgen Herb gives an insight into construction site preparation: Despite the fixed points of the Austrian BEV, despite APOS and comparable correction services, it is necessary to set up a separate GNSS system for each major construction project in order to synchronize the systems of different suppliers of surveying hardware and machine control systems. For this purpose, a separate GNSS receiver is installed on the construction site. Up to 11 GNSS sets are used simultaneously by polishers or foremen and on controlled machines. The accuracy is 1-2 cm in position and 2-3 cm in height and is sufficient for earthworks. For building construction projects, the surveying team uses one-man stations and carries out exact stakeouts and stationing.

The company relies on intelligent construction vehicles, so-called i-machines. They receive precise control data from Jürgen Herb's surveying department. The combination of sensors, GNSS navigation and 3D planning data enables the assistance systems to automatically guide earthmoving equipment such as crawlers, graders or excavators to the planned target surface. This allows work steps such as excavation, embankment filling or terrain cuts to be carried out with a high degree of accuracy - with significantly fewer manual corrections by the driver. "Short-term corrections to the planning can be imported via remote maintenance," explains the surveyor, "provided an internet connection is available."

Renovation of the retention basin on the Wien River

In a current project in Vienna-Auhof, the dividing walls and weir walls of six retention basins are being renovated. The damaged concrete is being removed (milled off) and replaced with reinforced facing concrete.

Controlled milling machines on hydraulic excavators are also used here. The concrete removal is continuously monitored on site using a theodolite. "With these dimensions, precise removal and application of concrete is economically necessary," Jürgen Herb points out. Precise calculations in advance are extremely important for this. The surveyor carried out preparatory transformations of the fixed points to the "Vienna zero" reference point using the rmDATA product.

Facts and figures on the Vienna River retention basin project

Construction of construction roads: 4,300 m
Repair of the weir sills: 500 m
Repair of the dividing wall: 1,200 m
Concrete removal by milling: 10,000 m³
White tank concrete: 12,000 m³
Wall formwork on one side with a height of up to 8m: 25,000 m²
Installation of reinforcing steel: 1,300 t

About GLS Bau und Montage GmbH

GLS Bau und Montage GmbH, based in Perg, Upper Austria, has been established as a full-service provider in the construction industry since 1997. The company combines building construction and civil engineering under one roof and covers a broad spectrum - from pipeline and traffic route construction, steel and bridge construction to structural engineering, hydraulic engineering, demolition and recycling. With its own production facilities and modern infrastructure in the Ennsdorf business park, GLS also realizes complex projects efficiently and reliably. Numerous certifications attest to the high standards of quality, safety and sustainability. Whether infrastructure, industrial plants or flood protection: GLS stands for engineering expertise, practical implementation and partnership-based cooperation - and accompanies construction projects of all sizes from planning to successful completion.