FHWA NDE CENTER RESEARCH & DEVELOPMENT

Evaluating Visual Inspection

The Visual Inspection method is by far the predominant nondestructive evaluation technique used in bridge inspections. Visual Inspection also serves as the standard by which all other nondestructive evaluation technologies may be compared. However, since the inception of the National Bridge Inspection Program in 1968, which mandated regular bridge inspections, a complete study of the reliability of the Visual Inspection method has not been undertaken. This study represents a crucial effort to assess the reliability of the Visual Inspection method.

The FHWA's NDE Validation Center was tasked with performing a thorough study of the state-of-the-practice of Visual Inspection. The experimental work plan involved 49 representative practicing bridge inspectors completing ten pre-defined inspection tasks at the NDE Validation Center. Quantifiable information regarding the inspection environment was collected in order to establish the influence of the inspection environment on the reliability of Visual Inspection. Additionally, extensive information was collected about each inspector's physical and psychological characteristics allowing the effect of human factors to be assessed.

The experimental program utilized seven of the NDE Validation Center (FHWA NDE Center) test bridges to conduct the field evaluation. The field investigation provided critical information related to the inspection environment and the inspector interaction within the environment. The laboratory experiments focused on specific aspects of inspection thought to influence reliability.

Inspectors participating in this study were asked to spend 2 ½ -days at the NDE Validation Center and the FHWA NDE Center test bridges performing the required tasks. They also underwent a number of tests to determine some of their physical and psychological characteristics. While in the field, the inspectors completed both Routine and In-depth Inspections on portions of seven of the FHWA NDE Center test bridges.

While at the FHWA NDE Center, the inspectors also received background information on other research work performed at Turner-Fairbank Highway Research Center and at the NDE Validation Center.

Read about the Visual Inspection Study:
Read about the Inspectors' Characteristics
Read about the Field Bridge Inspection Tasks
Look at additional pictures of the inspection
Visual Inspection Study Update

For more information, please contact either by e-mail or telephone.

Frank Jalinoos  (202) 493-3082

frank.jalinoos@fhwa.dot.gov

FHWA NDE Center Home | Research & Development | Facilities | Publications | Newsletter | Links | Contacts | DOT Home

http://www.tfhrc.gov/hnr20/nde/vi.htm