Nondestructive monitoring of subsurface damage progression in concrete columns damaged by earthquake loading

• A full-scale RC column was subjected to simulated earthquake loading.
• Testing was supplemented using a shear wave ultrasound array system.
• Reflectivity reconstructions showed damage before it was visible at the surface.
• Quantitative characteristics were developed to assess damage progression.
• The proposed method is nondestructive and requires only one-sided access.

The assessment of the structural integrity of infrastructure after extreme events is an important application of nondestructive technology. Advancements in elastic wave-based methods in recent years have allowed for productive and accurate quantitative analysis which was previously lacking. In this study, ultrasonic array measurements coupled with a modified signature analysis method were implemented for damage detection purposes. Full-scale testing of a reinforced concrete column subjected to simulated earthquake loading was tested using ultrasound nondestructive testing at various stages of loading. A signature analysis technique was adapted to create improved reconstructions and was coupled with a quantitative analysis incorporating Pearson’s correlation coefficient. The results demonstrated the ability to detect internal damages and defects prior to appearance on the surface using one-sided access, showing promise for health monitoring applications.