Scanning electron microscopes (SEM) are most often associated with criminal forensics and investigations, but they also have a place in transportation analysis and research. The article investigates how the transportation community might benefit from SEM, and provides some examples, such as: resembling a topographic view of an alien landscape, an SEM image can show small particles or components of deterioration before they cause safety risks on a bridge structure; SEM can help analyze crack failure, fatigue, and brittle fracture in steel structures, or provide quality assurance for paint applications. Some of the Federal Highway Administration (FHWA) research projects using SEM include: evaluation of the durability of both geosynthetic materials and Portland cement concrete; evaluation of bridge coatings and paints; recovery and disposal of hazardous materials like asbestosand lead-based paint; and, together with the Smithsonian Institution's Freer Gallery, study of ancient ceramic materials excavated in northern China. These examples represent just a handful of the numerous current and potential applications for the use of SEM in highway research and development. The benefits of applying SEM techniques to relevant research projectsreach beyond improved understanding of the physical and chemical processes that affect materials, they include enhancing the safety and durability of the transportation infrastructure.
Abstract