A crane fell onto a pier in British Columbia, smashing through the concrete and compromising the slab.

Situation

Xradar were called out to to perform a crack and void detection survey to ensure there were no large voids within the intact areas of the concrete pier.

Solution

Utilizing Ultrasound Pulse Echo to image the concrete, full 3D images of the slab were produced. A number of voids were identified within the slab and highlighted in a comprehensive report. This enabled the repair crew to focus their repairs on just the affect areas, reducing cost and saving time.

Xradar used a high frequency GPR survey to achieve the required accuracy and a mid-range frequency GPR to reveal information about the structural details underpinning the area. Several grids with evenly spaced lines were laid out resulting an approximately 350 sqm of total coverage.

The Xradar systems used were carefully calibrated onsite to ensure accurate depth measurements. Data was processed and compiled to produce contoured heatmap style results. Results were presented in a CAD workspace and digital reports delivered.

The Xradar survey was complimented with Vuit 3D laser scanning to achieve accurate, scaled georeferencing of our survey grids, and a convenient way to view and present the asphalt thickness results.

The survey revealed a distinct change in the asphalt thickness due to the structural change to the subsurface that was confirmed with the survey results from the mid-range frequency GPR. The data uncovered not only the asphalt thickness but also the nature and location of the subsurface features such as: beams, voids and structural slab changes.

3D Laser Scan, with Xradar results overlaid
Asphalt Thickness Map