What is the primary use of vibration testing in bridge inspection?

The primary use of vibration testing in bridge inspection is to check for structural soundness based on vibrating frequency. This method involves analyzing how a bridge responds to vibration, which can reveal important information about its integrity and overall health. Different structural elements will have specific resonance frequencies, and any deviations from expected frequencies may indicate issues such as deterioration, cracking, or other structural deficiencies. By carefully evaluating the frequency response, engineers can detect problems that may not be visible through standard visual inspections.

In contrast, the other options focus on different types of assessments. For example, measuring moisture content pertains to evaluating water infiltration and its effects on materials, while identifying flaws in concrete focuses on surface and subsurface defects. Determining the thickness of asphalt relates to pavement evaluations rather than structural health assessments. Vibration testing specifically targets the dynamic properties of a structure, making it particularly valuable for assessing the condition and stability of bridges.