Ground penetrating radar (GPR) is regularly applied to examine concrete structures such as walls, floors, columns and bridges. It has recently gained popularity for Concrete Scanning & Imaging . GPR has great advantages over more traditional methods including:
- Capability of greater depth penetration (up to 18 inches at high resolution)
- Ability to resolve second layer of rebar (subject to spacing)
- Ability to determine slab thickness
- Ability to detect air voids, conduits and pipes (including plastic), post tension cables, etc.
- Screed does not have to be removed to map rebar in floor slabs
- Generally only one-sided access is required
- Capable of producing depth slice images and 3D models
Historically only X-ray technology created a photographic image of the concrete interior however it required access to two sides of the structure and also involved the utilization of hazardous X-ray sources.
Detailed imaging of reinforcement is possible by scanning at close centres on a regular orthogonal grid. The results are processed using specialist software and depth slices or even a 3D model of the reinforcement may be made.
Alternatively, if depth and rebar spacing is required, this data could be shown graphically or exported into a spreadsheet for statistical analysis including contour plotting.