What is GPR Void Detection Survey?

Ground Penetrating Radar (GPR) technology in building inspection uses the emission and reception of electromagnetic waves to non-destructively and efficiently detect underground voids, delaminations, pipes, rebar, cracks, etc. It is particularly suitable for detecting voids beneath the ground surface (such as roads and bridges), leaks and collapse hazards in municipal pipe networks, providing high-precision two-dimensional/three-dimensional images. Combined with artificial intelligence, it enables rapid and accurate assessment of the quality and safety of underground structures, making it an important tool for modern infrastructure non-destructive testing.

Principle of GPR detection of voids:

1. Electromagnetic wave emission and reflection: The GPR equipment emits high-frequency electromagnetic waves into the ground.

2. Medium change: When the electromagnetic waves encounter the interface of different media (such as dense soil and voids, pipes), reflection occurs.

3. Signal reception and imaging: The receiver records the reflected signals, and through the propagation time and intensity changes of the signals, a two-dimensional/three-dimensional profile of the underground medium is formed.

4. Void identification: The void area has a large difference from the surrounding soil medium, which will produce a strong reflection signal, appearing as an abnormal feature on the radar image, thus identifying the depth, size, and location of the void.

Applications in building inspection:

• Road and bridge inspection: Detecting voids, delaminations, and cracks beneath bridge decks and roadbeds to determine whether they will cause road subsidence and collapse.

• Municipal pipe network inspection: Detecting leaks and damage in underground water pipes and drainage pipes, identifying pipeline locations, and preventing ground collapse caused by pipe network problems.

• Dam safety assessment: Detecting erosion, cracks, and voids inside dams to assess their flood control safety.

• Concrete structure inspection: Assessing the distribution of rebar, cover thickness, and internal defects in concrete.

Technical advantages:

• Non-destructive: No damage to the target structure, does not affect normal use.

• High efficiency: Rapid scanning of large areas, providing real-time data.

• High precision: Can identify small voids and fine structures (such as rebar).

• Intelligent: Combined with AI and big data, it enhances data analysis and early warning capabilities. Challenges and Development

Currently, combining robotics, acoustic technology, and artificial intelligence, the research team is working to establish a database of voids/leaks and develop a data-driven early warning system to improve the automation and predictive capabilities of detection, in order to address the challenges posed by aging urban underground pipeline networks.

If you would like to learn more about the classification of ground-penetrating radar (such as 2D, 3D, and dual-frequency) or specific application scenarios (such as roads and bridges), you can further search for relevant technical specifications and case studies.