Project: Concrete Void Survey of Slab on Grade

Xradar were recently hired by a BC company to determine the presence and location of any voids below or within the concrete slab on grade of a building.


A giant pulp mill in the interior of BC was preparing to install new machines and expressed concern about voids beneath the concrete slab, and the potential impact they would have on their new heavy machines.

Xradar was contracted by the mill’s engineering representatives to perform a full void survey of the mill using Xradar Enhanced Concrete Scanning.


The void survey covered multiple locations throughout the ground level of the building utilizing Xradar technology.

In addition to the void survey, our technician performed a 3D laser scan of the area, allowing the client to better reference any areas of corrosion and explore the site using a virtual walkthrough. The survey results were also overlaid on these images and highlighted in the below report extract.

The data was processed and analyzed and voids were identified below the slab in a number of locations. Some areas highlighted showed small air gaps between the concrete slab on grade and the soil beneath, however, sizeable voids were also detected, along with evidence of concrete deterioration.

Following the results of the survey a repair and strengthening strategy was planned to avoid any damage to the building and new machine installations.[

Extract from survey report[/caption]

For more information on voids and to arrange a void survey, get in touch with one of our Xradar technicians.