Using Tech to Map Infrastructure Deterioration

A rehabilitation project is currently underway on the bridge deck carrying I-87 over Pascack Road in New York. In order to quantify and map the concrete deterioration on the asphalt overlaid bridge deck, the project team turned to technology.

On this project, Infrasense and the crew used ground penetrating radar (GPR) to quantify and map. This was done at driving speeds using a vehicle-based system, which means no lane closures were needed. In addition to being used at high speeds, GPR also has the ability to penetrate and detect deterioration through the full thickness of the deck, regardless of the presence of an overlay.

The equipment used on this survey was a dual 2-GHz air-coupled horn antenna system manufactured by GSSI. The analysis was carried out according to ASTM D6087-08 using Infrasense’s software.

The bridge deck analysis was surveyed with 40 lines of GPR data, each representing a longitudinal cross-section through the deck. The cross-section shows the different structural layers of the bridge deck, including the bottom of the asphalt overlay, top reinforcing steel, and bottom of the deck.

Next, the amplitude of the layers is calculated and then quantities and maps of concrete deterioration, asphalt overlay thickness, and concrete cover are produced.

The end result is a more efficient way to gather all the data—without shutting down roads—leading to a safer and more productive jobsite.

Related Articles