Bridge Pillar Inspection Using Thermography and Multispectral Images

Abstract

Bridges play a vital role in the transportation sector, which is crucial to human life and the economy. To monitor the underlying deterioration of concrete bridges, this study investigates the potential use of unmanned aerial vehicles (UAVs) equipped with multispectral and infrared thermography sensors. The study area of this research was located at North-South Expressway Central Link (ELITE) Highway. A secondary multispectral and primary thermal images were used to inspect a bridge pillar’s concrete surface fault. Using low-altitude planes, a high-resolution thermal camera was used to capture thermal images during the inspection process. A software program was used to improve the photos and stitch them together to create a mosaic thermal image of the entire bridge pillar. The mosaic thermal imaging image was segmented using K-means clustering, with the image analysis using the highest value thermal pixel in the image as the seed pixel. The results were then verified using multispectral photos taken using a high-resolution digital camera to evaluate the state of the surface. This study has successfully demonstrated the utility of a UAV outfitted with high-resolution thermal infrared imaging for accurately assessing subsurface faults on bridge supports. The suggested methodology encourages a safe working environment, allowing for more frequent and less expensive bridge pillar inspections. Quick bridge condition inspections during various service live phases should be possible, effectively allocating funds for upkeep and repairs.