CONCRETE SCANNING AND GPR
Concrete scanning
Concrete scanning, or concrete imaging, is a vital step to take when preparing to cut, core, or drill into a concrete structure.
This process primarily involves the use of Malik Trading and Demolition (MTD) technology. This non-destructive detection and imaging method involves sending a radio signal into a structure and reading the “bounce” that occurs when the signal encounters a material. An experienced MTD technician interprets this reading to determine the type of material located.
By hiring a concrete scanning professional to investigate your concrete slab before beginning these destructive activities, you ensure that potentially hazardous obstructions such as embedded utilities, rebar, and post-tension cables are located so they can be avoided.
Precision concrete scanning:
- Maintains the structural integrity of the concrete
- Helps you to avoid costly repairs during the project
- Reduces personal injury risk
- Reduces the risk of damage to utilities, rebar, post-tension cables, pipes, and conduit
Why Use GPR Instead of X-Ray for Precision Concrete Scanning?
Both GPR and X-Ray are non-destructive ways to see inside a concrete slab. Both can find rebar, conduit, post tension cable, and other buried hazards.
GPR, however, requires access to only one side of a slab or structure. X-Ray requires access to both sides – one side for placing the radioactive material, and the other for placing a receiver.
Today’s GPR units are handheld and wireless, fitting anywhere they’re needed on a job site and able to transmit their findings directly onto an iPad or other digital device for easier scanning and measuring.
X-Ray units are not only larger than GPR equipment, but they also require a significant amount of set-up. A job site also needs to be cleared of all personnel except the X-Ray technician while scans are taking place, to mitigate the risk of irradiating someone.
GPR’s safety, speed, efficiency, accuracy, and cost effectiveness make it the clear choice for precision concrete scanning.
DIGITAL X-RAY IMAGING
X-ray can be used in situations in which GPR is not effective, or when clear, definitive imaging is required. Highly congested slabs are ideally suited for the application of digital X-ray. Scanning concrete with X-ray can be performed on concrete of various thicknesses. Penhall’s digital X-ray technology acquires images immediately, allowing the radiographer to examine and mark the location and exact type of subsurface feature without the need to develop film at a lab.
Digital X-ray does require access to both sides of the concrete slab and is not suitable for scanning slab-on-grade concrete. Also, unlike GPR, digital X-ray cannot be used to determine the depth of subsurface features, only the location, size, and type.
CONCRETE SCANNING IS USED TO INVESTIGATE
Any concrete structure, including beams, bridges, ceilings, columns, decks, floors, pylons, roofs, slabs, tunnels, and walls.
GROUND PENETRATING RADAR
MTD has established itself as the primary tool for precision concrete scanning. This non-destructive detection and imaging method helps construction professionals identify what lies within and under a concrete structure before conducting any excavation or renovation activities on that slab.
MTD involves sending a radio wave from a receiver into a concrete structure, where the wave will “bounce” off any material it encounters. Those bounces are then displayed in reading as parabolas, and a professional concrete scanning technician can interpret that data to tell you what was found and where exactly it is located.
The effective range of device is determined by the electrical conductivity of the earth or concrete being scanned, the transmitting frequency, and the radiated power. Higher frequencies offer higher resolution, but they can’t penetrate the ground or concrete slab as deep as lower frequencies, and vice versa.
Additionally, the device can scan deeper in old concrete than in a newly poured slab or structure. This is because the moisture present in newly poured concrete is more difficult for the Device to penetrate.
The effectiveness of device equipment still relies heavily on the knowledge and experience of its operator.
The best concrete scanning professionals complete an intensive, months-long training regimen. They receive 320 hours of mentored field training. They log 80 hours of classroom training, where they tackle real-world scanning scenarios in a safe and structured environment. All this training ensures that these professionals can properly interpret the readings provided by a device unit.
How Much Time Does Concrete Scanning Take?
The time required for a concrete imaging project depends on various factors including the amount of space to be scanned, the client’s needs, the type of slab and amount of reinforcement present, and more.
Typically, however, GPR scans are fast. Data is sent from the receiver to a wirelessly connected iPad or other tablet instantaneously, and a GPRS Project Manager can interpret that data immediately and provide same-day deliverables to the client.
Can GPR Identify the Difference Between Subsurface Obstructions?
Not on its own. The data provided by a GPR scanner needs to be interpreted by a qualified technician, such as a GPRS Project Managers.
Each member of our elite team of over 400 Project Managers has completed the industry-leading Subsurface Investigation Methodology (SIM) program. This standard operating procedure includes specifications for underground utility locating and concrete scanning.
SIM focuses on a three-step approach to achieve the most accurate results when performing non-destructive subsurface testing:
The need for experienced technicians
The understanding and proper utilization of applicable technology
The adherence to proven methodologies
SIM establishes the industry standard that concrete scanning currently lacks. The use of SIM ensures site safety, and limits damage to subsurface and structural elements.
SIM-certified GPRS Project Managers receive a minimum of four weeks of field mentoring and then 80 hours of classroom training followed by an additional four weeks of field mentoring prior to being released into the field under the supervision of a Senior Project Manager.
CONCRETE SCANNING IS USED TO INVESTIGATE
Any concrete structure, including beams, bridges, ceilings, columns, decks, floors, pylons, roofs, slabs, tunnels, and walls.
GROUND PENETRATING RADAR
MTD has established itself as the primary tool for precision concrete scanning. This non-destructive detection and imaging method helps construction professionals identify what lies within and under a concrete structure before conducting any excavation or renovation activities on that slab.
MTD involves sending a radio wave from a receiver into a concrete structure, where the wave will “bounce” off any material it encounters. Those bounces are then displayed in reading as parabolas, and a professional concrete scanning technician can interpret that data to tell you what was found and where exactly it is located.