Detection of underground objects
Till recently, the detection of underground objects, cables and wires beneath and along rail tracks was a relatively labour-intensive process. With substantial disruption of rail activity, the assumed location of objects was verified by manually digging trenches along the tracks. Grontmij and Ground Control GmbH have developed a method by means of which a reliable and safe pinpointing of cables and wires can be achieved using radar images, without compromising the availability of rail infrastructure in the process.

Radarscan
The system is based on the deployment of ground-penetrating radar. This method makes use of electromagnetic reflections: radar signals are transmitted into the ground from both sides of the track, using antennae. The signals are then reflected by subsurface objects, cables and wires. The reflections are then detected or intercepted by receiving antennae.
After computer processing, a detailed cross-sectional image of the subsurface is obtained, with all relevant cables, wires and objects. The system can be mounted on a train, thereby making it possible for subterranean radar surveys to be conducted at the speed of 40 km/h.

Subsurface inspection
Wires and cables in the subsurface constitute a significant risk to all civil engineering projects, unless their positions are meticulously charted. Grontmij possesses ultramodern subsurface imaging equipment with which detailed information about the underground can be obtained and charted. In addition to locating wires and cables, we can also conduct research into subsurface features, subsurface pollution and archaeological structures, as well as inspection of structures.

Risk management
Adequate insight into the nature and positions of all cables, wires and objects is essential to the commencement of all projects in the course of which the subsurface is stirred. This is not only necessary in order to safeguard against damage to these objects during excavation, but more importantly to avoid delays in rail traffic as a direct result of damage to signals and power lines, factors that are usually accompanied by high costs and damage to the corporate image. All of that can be prevented by conducting a thorough, reliable and meticulous subterranean survey prior to the start of operations.

Every survey is unique in itself. The Grontmij team of Radarscan specialists sits down with you to draft a bespoke plan of action designed to go the extra mile in reducing all imaginable risks to the execution of rail track projects to a bare minimum.

Benefits:

• Reduction of risks during the execution phase of the project. Continuous measurements ensure that there are no “blind spots” any longer.
• Meticulous: round-the-clock surveys make it possible for the data collected from the entire round of measurements to be charted uninterruptedly.
• Safety: no employees along the rail tracks
• No stirring of the ground