GPR and Post Tensioning Scanning

Introduction to Post Tension

Post-Tensioning (PT) is a method of reinforcing (strengthening) concrete or other materials with high-strength steel strands. The benefits post-tensioning brings to a structure include large open plan, column free floor spaces.

The technology reduces the amount of conventional reinforcement and concrete required thus delivering a more economical and environmentally friendly solution. With its varied depth and presence in slabs amongst reinforcing steel and other embedments GPR is the suitable technology to locate and avoid it. 

Please follow this link to read more about the GPR products offered by PCTE

Ground Penetrating Radar and PT

The Proceq GPR uses Ground Penetrating Radar (GPR) technology which uses radio waves to locate objects of differing dielectric constant. Therefore materials such as plastics, metals, and filling material can be located.

One of the main applications of GPR is to locate PT. Its antenna has the right frequency to develop a crisp image and at the same time get the necessary depth, this combination is a critical factor when locating PT.

Why? It is essential to differentiate the PT from the steel reinforcement in the concrete for Q&A or if drilling is needed. The Proceq GPR range is specifically designed for this type of application.

The example scans below demonstrate the types of data possible. In the left image rebar is shown i the top of the image. The PT duct is the large hyperbola at approximately 300mm. The right hand image is the same data shown in migrated mode. This more clearly shows the position of the PT duct.

Help and Training

PCTE can also provide training with every GPR sold. Our experienced trainers have a range of techniques used specifically for locating PT, even in difficult areas.