Investigation of the Mechanism of Hidden Defects in Epoxy Asphalt Pavement on Steel Bridge Decks Under Moisture Diffusion Using Nondestructive Detection Techniques

This study conducts a rigorous analysis of the moisture diffusion mechanism that undermines the adhesive layer of epoxy asphalt (EA) pavement on steel bridge decks, thereby fostering latent distresses. Furthermore, a novel and highly efficacious approach for detecting these concealed distresses is introduced. The findings of water vapor permeability tests conclusively reveal that the moisture diffusion coefficients of the upper and lower layers of the EA pavement stand at 0.1238 mm²/s and 0.0879 mm²/s, respectively, highlighting this disparity as the primary trigger for concealed issues like pavement delamination and swelling. Leveraging the combined capabilities of three-dimensional ground-penetrating radar (3D-GPR) and infrared thermography, this research reliably detects, identifies, and pinpoints concealed defects at three strategic locations on the steel bridge deck. The integration of these two technologies has exhibited remarkable proficiency in identifying concealed damages. Consequently, this study lays a substantial foundation for evaluating and detecting concealed distress in EA pavements atop steel bridge decks.