GPR or Ground Penetrating Radar scanning is the industrial standard to see through the concrete structure. It is a non-destructive method of concrete scanning that is used to inspect the concrete structure, measure slab thickness, and locate rebars, PT cables, conduits, voids, and other utility installations. The usual question of the people is— how deep can I see with a GPR, or I am not able to clearly locate the utilities. What are the factors that affect the accuracy of the GPR?   Well, there are many factors that can affect the accuracy of the GPR and the depth a GPR can see. We will look at the four main factors.

  1. Type of Soil
  In ideal conditions where the soil is non-conducive and dry, such as sandy and silty soils, a GPR can detect the elements as deep as 100 meters. On the other hand, in conducive soils like clay, the depth and accuracy of GPR reduced significantly. Not just that, the presence of a metal obstacle can also affect the depth as it will not allow the GPR signal to pass through it.

  1. External Condition
  External conditions like bad weather and the presence of noise can also affect the accuracy of the GPR. When the moisture is absorbed by the soil, it impacts the conductivity of the soil, which in turn impacts the depth and accuracy of the GPR. Similarly, if there is a strong presence of noise or sound frequencies in the area to be scanned, it can impact the results of the GPR.

  1. Skills of Interpreter
  The skills of the interpreter also impact the accuracy of the results. GPR does not tell about the type of obstacle detected. It only tells about the frequencies. It is the GPR engineer who has to interpret the graphs and tell about the location and nature of the obstacle. Anomalies present on the site may also result in inaccurate results, but an experienced engineer considers the anomalies in the account to provide the most accurate results.

  1. Technological Limitations
  GPR technology has come very far. Today's advanced GPRs can even detect the PVC and plastics buried in the soil or concrete, but old GPRs may not be able to do so. Similarly, the signal strength of a GPR also plays a role in determining the depth and accuracy of the results.   If we talk about us, at Concrete Insight, we use GSSI StructureScan Pro SIR4000 that can be used to accurately detect metal, rebars, plastic, PVC, air pockets, voids and geological features. It is among the most advanced GPR radars in the market that provide accurate results.   If you need GPR concrete scanning services, you can contact our GPR concrete scanning experts. We have more than 25 years of experience in concrete scanning.