High-resolution 3D condition survey of a masonry arch bridge using Ground Penetrating Radar

Condition surveying is essential before rehabilitation and modification of a structure. It implies information collection and analysis for structural performance evaluation. Common condition surveying often requires obstructive and invasive techniques that can affect the structure’s integrity. Also, the extent of internal disorders and their distribution in the structure is not obtained. The use of non-destructive techniques combined with external analysis, can provide useful information for structural condition surveying. This paper presents the application of Ground Penetrating Radar for the condition survey of a massive natural stone masonry bridge with twin large span arches. Emphasis is placed on the determination of the condition of the arches. The paper describes the processing steps leading to a high-resolution 3D reconstitution of spatial and structural information for disorder mapping. Benefits and limits of this novel representation method for massive bridge structures will be reviewed.