Updating Bridge Deck & Approach Roadway Inspections Can Save Lives!

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We offer the most advanced nondestructive testing methods to assess the integrity of your assets worldwide.

Ground penetrating radar

Understanding the current condition of our infrastructure is vital in preserving infrastructure assets worldwide. Updating current inspection methods to utilize technology and robotics can save billions in untimely replacements, help extend the service life of critical infrastructure assets and better protect the traveling public.

Current Visual Bridge Inspections

Visual inspection is a simple method that allows inspectors to map spalling, cracks, and potholes on bridge decks visually. The technique cannot be used to assess the interior of the concrete structure.

Visual inspections are the least efficient and most commonly employed. A visual inspection addresses problems after they have become conspicuous, dangerous, and expensive to fix.

Isn’t it just common sense that once there is a visible crack that it is too late?

Locating deficiencies early in their lifecycle makes it less costly and more efficient for asset owners to budget for repairs and more efficiently deploy maintenance crews for repairs. Unfortunately, current manual inspections are just no longer enough.

Chain Dragging

Current manual inspections are visual and typically include an inspection method called chain dragging.

Manual, Subjective, and only used in areas where visually there may already be issues.

Chain dragging

Chain dragging is an acoustic technique where the human ear detects changes in pitch or sound made by a chain being dragged over the surface of a structure. It detects delamination which describes the splitting of a structure into layers or the separation of a coating from a substrate. Bridges suffer elimination due to freezing and thawing, and corrosion of the structure’s reinforcing steel.

The technique is cheap and requires less training because the areas of deterioration are located just by tone. However, chain dragging does not work on structures with asphalt overlays. Additionally, hearing biases can lead to different delamination maps. The results of the technique can also be affected by outside sources of noise such as traffic. Chain dragging only detects existing delamination which occurs after the rebar has been corroded significantly.

The method is manual, subjective, and does not provide enough data to accurately assess the structure or help the asset owner develop an action plan for repairs.

Updating 50 Antiquated Inspection Methods With Modern Technology and Robotics

Current Method of Chain Dragging

BridgeScan® Complete Bridge Deck Assessment

Old bridge inspection method

Current Chain Dragging

Spot Checks
Subjective Results

Ground penetrating radar inspections

BridgeScan ®

Peers through the deck.
Locates delamination, rebar placement, water intrusion, voids, and deterioration.
Heat maps and quantitative data.

Can provide material quantity and budgets for repairs


Current GPR Does Not Compare To BridgeScan® for bridge inspections. 

A newer approach to bridge deck assessments is Ground-penetrating radar (GPR). GPR  utilizes a high-frequency radio signal that is transmitted to the ground while the reflected signal is captured by a receiver and stored on digital media. A computer system determines the time taken for a pulse to travel to and from the target and shows its location and depth.

Reflected signals are interpreted by the equipment and displayed on a screen. The reflected signals are used to detect changes in material, cracks, voids, and objects.

The technique is used to assess the uniformity and quality of concrete highway surfaces and detect the deterioration of bridge decks. GPR for bridge surface measurement can be air-launched or ground-coupled.

Bridge inspection with robot

Additional posts about bridge inspections and robotic infrastructure inspection services:

Ground-coupled GPR uses an antenna placed close to the surface while air-launched systems use directional antennas that are aimed at the surface of the structure from the height of between 30 and 40 centimeters. Ground-coupled antennas are slow but less prone to radio frequency interference. Air-launched antennas can be used even when traveling at 120 kilometers per hour.

The location of objects such as post-tension cables, conduits, and rebar embedded in the concrete uses a high-frequency GPR system. The data can be gathered in a grid format to produce a map of any targets on the concrete, or simple line scans to determine the thickness of the concrete. While acoustic is subjective, GPR is more quantitative and is not affected by noise.  GPR however provides a lot of data not easily interpreted by asset owners.

Ground-penetrating radar has many other applications apart from nondestructive testing of bridge decks and approach roadways. The applications include the study of ice, groundwater, bedrock, and soil. It is also used in the mapping of archaeological features, detection of tunnels and mines by the military, and location of underground utilities.

For bridge decks, GPR is not a technology that will provide the Department of Transportation the quantitative data nor the format that they would need to interpret areas of concern.  As this technology advances it may become more decipherable for the use of bridges on a larger scale.

Introducing BridgeScan®

The latest in the bridge deck and approach roadway inspection services. 

Infraspect, Infraspect’s Bridge condition assessment Inspections provide crucial information to asset managers and engineering firms. The comprehensive assessments provided by BridgeScan® allow the asset owners to develop an action plan for accurate repairs before the structure becomes critical.

The information is used to budget for maintenance and extends the life expectancy of structures through early detection and deterioration repair. Infraspect’s BridgeScan® has been validated by the DOT and through coring to prove up submitted results.

Exceeds AASHTO and FHWA guidelines showing 12 levels of deterioration. See below specific graphic interpretation of BridgeScan® results. Coring proved 100% accuracy in both good and deteriorated sections.

Ground penetrating radar

The BridgeScan® unit is can be manual or robotically controlled. The reports provide quantitative information that goes way beyond current bridge deck inspections.

The safety of our infrastructure will come by first understanding its current condition and then monitoring deterioration progression over time. BridgeScan® can locate deterioration, delamination, rebar placement, water intrusion, underground compactness, and more. Infraspect can even provide materials required for repairs and budgets for those repairs with their reports.

Submit a scope of work or ask to review a Sample Report!

Speak to one of our Robotic services experts: Call (888) 423-2136 Ext. 24

By utilizing modern technology and managing deterioration progression over time (before cracks are formed or sinkholes occur), asset managers can better budget for maintenance and repairs.


Prove up provided 100% accuracy based on 3rd party cores.

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Infraspect is a complex bridge inspection, non-destructive testing (NDT), and robotic engineering company. Infraspect utilizes advanced non-destructive testing and robotic technology to produce condition assessment reports that determine the condition and deterioration of today’s infrastructure.

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