Laser-Based Instrumentation for Highway Bridge Applications

One of the goals of the Federal Highway Administration (FHWA) Nondestructive Evaluation Validation Center (NDEVC) is to enhance the types of tools available to bridge inspectors. Instrumentation and techniques that provide more information about the condition of a structure are a focus of the center. Systems are currently being developed that greatly increase the amount of data that can presently be gathered with conventional instrumentation and in some cases provide types of data previously impractical to obtain. One of these systems is a laser-based instrument that has been successfully used in a number of applications related to highway bridges. Four of the main projects related to this laser system are presented as an example of the capabilities of the instrumentation. These applications include laboratory testing on a full-sized steel curved girder bridge, measurement of the as-built state of bridge abutments in a full-sized test bridge, load testing of in-service bridges, and tests related to the fabrication of steel bridges.