Radiographic Testing
High-Resolution Internal Imaging of Dense Reinforcement Zones
Radiographic testing uses X-ray or gamma radiation to produce high-resolution images of internal structural features, reinforcement layout, tendon condition, grout voids, and embedded items, with clarity that exceeds GPR in heavily congested reinforcement zones. The technique transmits radiation through the structural element from one side and captures the transmitted image on a detector or film on the opposite side, producing a shadow image analogous to a medical X-ray.
TRSC deploys radiographic testing where GPR resolution is insufficient, typically in heavily reinforced connection zones, post-tensioning anchorages, and areas where multiple reinforcement layers create GPR signal interference. In these situations, radiographic imaging provides the definitive reinforcement mapping that structural analysis requires. The technique can also assess the condition of post-tensioning tendons within grouted ducts, detecting wire breaks, corrosion, and grout voids that other methods cannot reliably identify.
Radiographic testing requires access to both sides of the element being imaged, radiation licensing, and exclusion zones during exposure. These operational constraints make it significantly more complex and costly than GPR, which is why TRSC uses it selectively, only where the additional resolution justifies the additional complexity. Typical applications are limited to specific connection details or tendon locations where GPR results are ambiguous.
All radiographic testing conducted for TRSC is performed by licensed radiation operators in compliance with Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) requirements and relevant state radiation safety regulations. TRSC coordinates exclusion zones, safety protocols, and scheduling to minimise disruption to building operations during radiographic surveys.
Speak with an RPEQ-qualified structural engineer about deploying this technology on your asset.
Applications
Congested Reinforcement Imaging
Producing clear images of reinforcement layout in heavily congested zones, beam-column connections, transfer structures, and complex junction details, where GPR resolution is insufficient.
Post-Tensioning Tendon Assessment
Imaging grouted post-tensioning tendons to detect wire breaks, corrosion, and grout voids within ducts, critical for assessing the structural integrity of post-tensioned structures.
Grouting Verification
Confirming complete grout fill in post-tensioning ducts, precast connections, and masonry cavity fills where incomplete grouting affects structural capacity or durability.
Weld Inspection
Assessing weld quality in steel structural connections, detecting incomplete fusion, porosity, slag inclusions, and cracking in critical load-bearing welds.
Embedded Item Location
Locating and identifying embedded items (fixings, brackets, services) within concrete elements where GPR signal interpretation is ambiguous.
Forensic Investigation
Producing high-resolution images for forensic structural investigation where the exact internal condition of a structural element is critical to determining the cause of distress.
Frequently Asked Questions
When is radiographic testing used instead of GPR?
Radiographic testing is used when GPR cannot provide sufficient resolution, typically in heavily reinforced zones where signal clutter prevents reliable interpretation, or for post-tensioning tendon assessment within grouted ducts. For standard reinforcement mapping, GPR is preferred due to its lower cost, single-side access, and lack of radiation concerns. TRSC recommends radiographic testing only where the investigation question cannot be answered by other means.
Is radiographic testing safe?
Radiographic testing involves ionising radiation and is subject to strict safety regulations. All testing is performed by licensed operators, with exclusion zones enforced during exposure. Outside the exclusion zone, radiation levels are below background. TRSC coordinates safety protocols, scheduling, and building management notification to ensure safe operation in all environments.
How long does radiographic testing take?
Each radiographic exposure takes 1–10 minutes depending on element thickness and source type. Setup, positioning, and safety exclusion zone establishment add significant time to each exposure. A typical investigation involving 10–20 exposures may require one to two days on-site. Digital radiography provides immediate results; film radiography requires off-site development (1–2 days).
Deploy X-ray on your asset
Every investigation begins with a direct conversation with an RPEQ-qualified structural engineer. No sales intermediary, contact TRSC to discuss whether radiographic testing is appropriate for your structural question.