Do you need to locate embedded metal in buildings? Sandberg offer GPR surveys to detect embedded metal in masonry. These are particularly suitable for heritage structures, where metal was often used to form a structural frame or to strengthen and fix masonry blocks.

Embedded metal in masonry

Embedded metal has been used for strengthening masonry structures for hundreds of years. Most commonly, the embedded metal comprises:

  • Structural I beams and columns
  • Metal dowels
  • Pins and cramps
GPR Radargram showing an embedded steel column in a masonry wall
Radargram showing an embedded steel column in a masonry wall

With time, metal deterioration, notably corrosion, can occur. Remedial works, comprising repair and preventative measures, are eventually required. Our non-intrusive GPR surveys help Structural Engineers identify the cause of the problem and decide on the necessary remedial action.

Site survey

Sandberg embedded metal location investigation surveys typically use a combination of metal detection and Ground Penetrating Radar (GPR) scanning techniques. Both are non-intrusive.

Metal detection offers a quick method to identify areas of metal; however, most metal detectors are electromagnetic and will only detect ferrous metals. They will not detect stainless steel or brass.

GPR will detect all metals and provide information about depth, section, and approximate size. It can also help determine construction detail and thickness and detect other features, such as voids.

GPR surveyor scanning the facade of a London building to locate embedded metal in the masonry
GPR scanning to locate embedded metal in masonry

The GPR survey can either utilise single scan lines collected as required, for example, along mortar beds, or on a regular orthogonal grid to provide detailed coverage of a nominated area. We record the position of scan lines and distances relative to suitable fixed reference points. This enables accurate positioning of detected embedded objects.

We interpret the GPR data on-site in real-time to provide instant results. However, better results can sometimes be achieved with off-site analysis. In these cases, we save the GPR data electronically and undertake off-site processing, analysis, and interpretation.

Find out more about Ground Penetrating Radar and how it works.

Survey deliverables

We present our interpretation results in a comprehensive factual report issued in pdf format. Depending on the client’s preferences:

  • We can mark up the position of detected embedded metal in situ.
  • Mark the results on suitable CAD drawings.
  • Or, if required, do both.
CAD plot of building facade with detected embedded metal marked up.
CAD extract with detected embedded metal in the masonry building façade marked up (click on image to see larger cersion)

We also include details of other detected features and anomalies if relevant. Where applicable, we also issue the original CAD drawings in AutoCAD .dwg format.

Need more information?

Contact us

Contact us to find out more about our GPR surveys to Locate Embedded Metal in Masonry and how we can help you:

Telephone: 0207 565 7056

Information sheet

Download our information sheet about GPR surveys to detect embedded metal in masonry.

Are you wondering what else GPR can be used for? GPR surveys can investigate the subsurface and detect unseen features. Learn more about our most popular GPR surveys.