Concrete GPR Testing
Atlas Engineering and Technology Group provides concrete Ground-Penetrating Radar (GPR) testing services across Sydney and the surrounding regions. Our GPR surveys deliver fast, accurate, and non-destructive insight into the internal condition of concrete structures, helping engineers and contractors make informed decisions before cutting, coring, or undertaking remediation work.
What Is Concrete GPR Testing?
Ground Penetrating Radar is a non-destructive testing (NDT) method that uses high-frequency electromagnetic pulses to image the internal structure of concrete. The radar antenna transmits short pulses of energy into the concrete, and as these pulses encounter changes in material properties, such as reinforcement, conduits, voids, or layer boundaries, a portion of the signal is reflected back to the antenna.
The reflected signals are processed to produce a cross-sectional profile of the scanned area, revealing the location and approximate depth of embedded objects and anomalies.
Why Use GPR for Concrete Testing?
Traditional methods of locating embedded items in concrete, such as exploratory coring or demolition, are invasive, time-consuming, and carry risk. GPR offers a safer and more efficient alternative by allowing technicians to see beneath the surface without causing damage. This is particularly valuable when working near live services, post-tensioned tendons, or in occupied buildings where disruption must be minimised.
Key Benefits of Concrete GPR Testing
- Completely non-destructive (no cutting, drilling, or coring required during the survey)
- Rapid data collection across large areas with minimal disruption to site operations
- Real-time results allowing immediate on-site decision-making
- Capable of detecting both metallic and non-metallic targets
- Safe to use (no radiation hazards, unlike radiographic methods)
- Suitable for scanning from one side of a concrete element only
Common Applications
- Locating reinforcement bars, mesh, and post-tensioning tendons prior to coring or cutting
- Identifying embedded conduits, pipes, and electrical services
- Measuring concrete cover depth to reinforcement
- Detecting voids, delaminations, and honeycombing within concrete elements
- Mapping slab thickness and layer interfaces
- Structural condition assessments for refurbishment, strengthening, or demolition planning
- Pre-purchase and dilapidation surveys
- Quality assurance verification of reinforcement placement during or after construction
Our GPR Testing Process
- Pre-survey consultation to define the scope, objectives, and access requirements
- Selection of the appropriate antenna frequency based on the target depth and resolution requirements
- Establishment of a survey grid or scan lines on the concrete surface
- Data acquisition using calibrated GPR equipment, with scans conducted along defined paths
- Real-time on-site interpretation to provide immediate feedback where required
- Post-processing and detailed analysis of recorded data
- Preparation of a comprehensive report including annotated scan images, target locations, estimated depths, and recommendations
GPR Capabilities and Limitations
Understanding what GPR can and cannot achieve is important for setting appropriate project expectations:
| Aspect | Detail |
| Penetration depth | Typically effective to depths of 300–600 mm in concrete, depending on concrete condition and antenna frequency |
| Resolution | Higher frequency antennas provide greater resolution for shallow targets; lower frequencies achieve deeper penetration with reduced resolution |
| Metallic targets | Reinforcement, mesh, dowels, and metallic conduits produce strong, clearly identifiable reflections |
| Non-metallic targets | Plastic conduits, voids, and changes in material density can be detected, though reflections may be weaker |
| Limitations | Dense reinforcement congestion can obscure deeper targets; wet or highly chloride-contaminated concrete may reduce signal penetration; interpretation requires experienced operators |
Relevant Standards
Our GPR testing services are carried out with reference to applicable Australian and international standards and guidelines, including ASTM D4748 (Standard Test Method for Determining the Thickness of Bound Pavement Layers Using Short-Pulse Radar), ASTM D6432 (Standard Guide for Using the Surface Ground Penetrating Radar Method), and relevant Concrete Institute of Australia and Australasian (NDT) Society publications.
Why Choose Atlas Engineering and Technology Group?
Atlas delivers GPR testing with experienced, qualified technicians who understand both the capabilities and limitations of the technology. We use current-generation GPR equipment suited to a range of concrete applications, from thin slabs through to deep structural elements. Our team works closely with structural engineers, contractors, and building managers throughout Sydney to ensure that GPR data is accurate, clearly presented, and directly useful for your project needs.
Contact us today to discuss your concrete GPR testing requirements or to request a quote.