Detecting Voids In Concrete Slabs

Void detection is an important task for anyone who needs to know the location and extent of underground voids, sinkholes, and subsidence. With the help of Ground Penetrating Radar (GPR), you can scan an area of ground and get valuable information about what lies beneath.

GPR is a non-destructive and non-intrusive method of underground void detection. It works by transmitting an electromagnetic signal into the ground and recording the reflections. The reflections are caused by any changes in the below-surface environment, making GPR capable of detecting underground features such as sinkholes, voids, and subsidence.

One of the key benefits of using GPR for underground void detection is that it’s a cost-effective and low-risk way to scan large areas. GPR is a relatively lightweight equipment that can be used to scan any size area, without causing any damage to the surface being surveyed. It’s also a fully non-destructive and non-intrusive technology (NDT) which makes it a safe option for those who want to minimise the impact of their survey on the environment.

A GPR survey to detect underground voids is usually performed using handheld equipment like the IDS-Georadar C-Thrue, or the Proceq GS8000. The survey is performed by collecting parallel lines of GPR data in two axes to form a grid. The data collected is then processed and interpreted both on site using augmented reality, or in our office using our processing software, to form a 3D image. With the help of this 3D image, it’s possible to detect and track underground features such as voids, sinkholes, cold joints, and subsidence.

GPR has also been used to detect shallow voids and sinkholes in concrete and road structures, as well as man-made voids such as underground tanks, basements, culverts, mine shafts, and gas pipes. In one case, South-East Scanning was engaged to scan a series of Besser block walls at a client site in Brisbane to determine the extent of their filling. It was discovered that a series of wall sections were not filled due to errors in the concrete pour. This survey enabled the client to quickly identify the sections that needed filling, and determine which sections of the wall were sound to satisfy the demands of the engineers overseeing the project.

The results of a GPR survey of underground voids and subsidence are delivered in the form of a comprehensive report. The final output may vary depending on the best way to represent the information in a way that addresses client needs.

GPR is a highly effective method for underground void detection. It’s a low-risk, cost-effective, and non-destructive way to scan large areas and get valuable information about what lies beneath. With the help of GPR, you can be sure that your underground environment is safe and secure. 

The team at South East Scanning conduct this kind of check frequently and are equipped to help you. Reach out to us today!