Concrete Scanning Explained
What is concrete scanning?
Concrete scanning is the use of ground penetrating radar and other equipment to detect materials or voids within a concrete slab.
What can you find when scanning concrete?
Concrete scanning can detect rebar, post-tension cables, electrical conduit, and voids. It can also be used for structural review including concrete slab measurement and rebar spacing.
When do you need to scan concrete?
Concrete should be scanned before any destructive work is performed. This can include coring, drilling, cutting, and other activities which compromise the concrete’s strength.
Why do you need to scan concrete?
When concrete is scanned all major components within the concrete are marked out. This helps prevent damage to items such as rebar or conduit when performing destructive work.
Why is concrete scanning a safety concern?
Concrete scanning enables you to visualize major structural components within concrete. Markings allow you to avoid these areas when performing invasive work, preventing damage to the concrete structure. Damage to rebar and post-tension cables can be extremely dangerous, potentially causing immediate structural failure and injuring or killing those on site. Damage to electrical services within the concrete can cause electrocution or death.
How do you scan concrete?
Concrete is scanned with the use of ground penetrating radar. A device is passed over the concrete’s exposed surface, sending a signal into the concrete. The signal is deflected back to the device in different patterns depending on what type of material is found in the concrete and how deep the material is. An experienced technician will be able to determine the type and location of the material based off of this reading.
Can ground penetrating radar see through concrete?
Ground penetrating radar is effective at penetrating concrete in order to determine what is inside of it. GPR can be used to detect any non-concrete material or voids within.
Is it possible to scan vertical surfaces or ceilings?
Yes, GPR equipment is regularly used to scan for the location of rebar in concrete columns and walls. It can also be used to scan the underside of a floor to mark out the reinforcing steel and any embedded conduits.
How do you differentiate between rebar and conduit?
Rebar and conduit produce similar GPR readings. It is possible to identify rebar by its pattern and spacing. A break in the rebar often means that conduit is present.