01090959

Component

Nondestructive Testing (NDT) has become one of the most commonly used structural health assessment techniques. The continuing demand for a robust, reliable and cost-effective tool fuels the research in this area which benefits from the contribution of new methods and development of new technologies. The main application of NDT in civil engineering mostly focuses on structural damage assessment, determination of material properties and location of reinforcing bars in concrete slabs and bridge decks. The acoustoelastic effect was also used to investigate the stress level of different structural materials. However, the change in the wave velocity was the main parameter taken into consideration and related to the stress state of the tested material. This paper presents the results of an experimental study that investigates the changes in the energy and peak amplitude of ultrasonic signal echoes due to the stress state of steel under uniaxial tension. Ultrasonic signals, acquired from steel specimens before and after yield with a specially built testing system, were investigated in both the time and the frequency domains using digital signal processing (DSP) techniques. The results reveal that the tension yield state of steel can be detected using ultrasonic NDT.

01084478

08-0624

English

17p

2008

Transportation Research Board 87th Annual Meeting

DVD

Figures (7) ; Photos (1) ; References (16) ; Tables (2)

Digital communication systems; Maintenance; Monitoring; Nondestructive tests; Reinforcing bars; Signal processing; Steel; Time domain analysis; Ultrasonic tests; Uniaxial stress

Bridges and other structures; Design; Highways; Maintenance and Preservation; I24: Design of Bridges and Retaining Walls; I61: Equipment and Maintenance Methods

Transportation Research Board Annual Meeting 2008 Paper #08-0624

TRIS, TRB

Jan 29 2008 2:57PM