Post-Tension Scanning – Uses & Technical Details

What is Post-Tension Scanning?

Post-tension scanning is a non-destructive testing (NDT) technique used to locate post-tensioned (PT) cables, tendons, and ducts within concrete slabs or structural members. This is critical for safe cutting, coring, drilling, or renovation work in post-tensioned structures.

It typically uses Ground Penetrating Radar (GPR) or X-ray scanning to map internal steel layouts without damaging the structure.

Primary Uses of Post-Tension Scanning

1. Prevention of Accidental Damage

Cutting or coring into PT cables without knowing their location can cause serious structural failure, injury, or cable rupture. Scanning ensures safe execution of penetrations or modifications.

2. Concrete Coring and Drilling

Before installing HVAC, plumbing, electrical, anchor bolts, or other inserts, scanning is used to avoid hitting tendons, rebar, or conduits.

3. Structural Assessment and Repairs

PT scanning helps evaluate the condition and alignment of cables in deteriorated or damaged structures. It is crucial for as-built verification and integrity assessments.

4. Renovation or Retrofitting Projects

During refurbishment of PT slabs (e.g., for elevators, openings, or load changes), accurate scanning allows for modifications without compromising strength.

5. Mapping As-Built Cable Layout

Often, PT cable locations differ from original drawings. Scanning produces as-built records for facility management, future repairs, or documentation.

6. Forensic Engineering and Structural Investigation

In failure analysis or investigation of distressed structures, post-tension scanning reveals missing or failed tendons, improper layouts, or voids.