Call Or Email
(770) 569-1111
Click to Email

Metal Pan, Wire Mesh, and Ground Penetrating RADAR (GPR)

  • News

Metal Pan Wire Mesh and Ground Penetrating RADAR GPR

This article explains something we get a lot of questions about, or that customers in the past have just assumed would not work. How does GPR work with metal pan?
 
Typical metal pan construction is a thin layer of sheet metal with a high section and a low section, then offset just above the metal pan is a layer of reinforcing steel that is normally wire mesh. (bottom left image)
 
(top left, top of the slab with wire mesh pattern marked out)
(top right, the bottom of slab showing the metal pan)
 
A sort of worst-case scenario that people who have only a basic understanding of GPR would think, is that a metal pan floor with layers of wire mesh would be very hard, if not impossible to scan. For example, GPR reflects when it hits metal, so the signal cannot penetrate metal pan and all the wire mesh would cause interference and would make the signal extremely difficult to read.
 
 This is not the case.


Unlike X-ray, we only need access to the top of the concrete slab. While we cannot see through metal pan, that issue is irrelevant due to the metal pan being located at the bottom of the slab. We just need to see down to it.
 
In the graphics above you can see the green line of the profile of the metal pan (top right). This corresponds with the green line on the screen where we can see clearly down to the metal pan and the high/low pattern of it as well (bottom right). Everything in the blue outline area is the concrete layer. This is super clear and empty, and any PT cables or power conduits present would leave very large and noticeable hyperbola.
 
Wire mesh, like any metal, will reflect our signal. This is not an issue because it is thin and can be filtered almost completely out. The scan screen shown is from a spot with an overlap of wire mesh but with the proper filters applied we can get a clean image of the area we are inspecting.
 
Because of the metal pan, everything below the green line is irrelevant because it is just the “ringing effect” of the signal reflecting off the metal pan. This happens when the metal acts like a radio antenna and rebroadcast the signal.
 
In cases were metal pan is not used we can see all the objects connected to the bottom of the slab that are not embedded within. This can be walls or runs of conduits or junction boxes, and we will mark them out as being under the slab without ever having to go below. 
 
All these items are clearly visible from the floor below and can be inspected visually if access to the floor below is available. If requested these can be added to the report if metal pan is present.
 
Metal Pan with wire mesh is no problem for an experienced operator with the right equipment. We have done thousands of scans on this type of slab and have no problem guaranteeing our work.

 Ground Penetrating Radar - Archaeology - GPR - GPR Concrete Scanning - Geophysical Survey - Structural Analysis  - gpr concrete scanning

  • This email address is being protected from spambots. You need JavaScript enabled to view it.

  • Georgia # (770) 569-1111
  • North Carolina # (704) 247-7054
  • Tennessee # (615) 823-3460
  • Alabama # (205) 255-1765
  • Flordia # (904) 267-1568
  • South Carolina # (843) 800-8553
  • Corporate Office:
    1825 Lockeway Drive
    Suite 206
    Alpharetta, GA 30004

NORTH CAROLINA
Charlotte city Raleigh city Greensboro city Winston-Salem city Durham city Fayetteville city Cary town Wilmington city High Point city Greenville city Asheville city

SOUTH CAROLINA
Charleston Columbia North Charleston Mount Pleasant Rock Hill Greenville Summerville Goose Creek Sumter Hilton Head Island Spartanburg Florence Myrtle

TENNESSEE
Nashville-Davidson Memphis Knoxville Chattanooga Clarksville Murfreesboro Franklin Jackson Johnson City Bartlett Hendersonville Kingsport Smyrna Collierville Cleveland

GEORGIA
Atlanta Augusta-Richmond County Columbus Macon-Bibb County Savannah Athens-Clarke County Sandy Springs Roswell Johns Creek Warner Robins Albany Alpharetta

FLORIDA
Jacksonville Miami Tampa Orlando St. Petersburg Hialeah Port St. Lucie Tallahassee Cape Coral Fort Lauderdale Pembroke Pines Hollywood Miramar Gainesville Coral Springs

ALABAMA
Birmingham Montgomery Huntsville Mobile Tuscaloosa Hoover Dothan Auburn Decatur Madison Florence Phenix City Prattville Gadsden Vestavia Hills Alabaster 

 Ground Penetrating Radar - Archaeology - GPR - GPR Concrete Scanning - Geophysical Survey - Structural Analysis  - GPR Concrete Scanning

© Copyright 2019, Xenogenesis llc. All Rights Reserved