STRESS INFLUENCE PLANE AT ORIGINATING POINT OF FATIGUE CRACK PROPAGATING INTO DECK PLATE OF STEEL PLATE DECK AND ITS APPLICATION

Piezoelectric transducers are convenient enablers for generating and receiving Lamb waves for damage detection. Fatigue cracks are one of the most common causes for the failure of metallic structures. Increasing emphasis on the integrity of critical structures creates an urgent need to monitor structures and to detect cracks at an early stage to prevent catastrophic failures. This paper presents a two-dimensional (2D) cross-correlation imaging technique that can not only detect a fatigue crack but can also precisely image the fatigue cracks in metallic structures. The imaging method was based on the cross-correlation algorithm that uses incident waves and the crack-scattered waves of all directions to generate the crack image. Fatigue testing for crack generation was then conducted in both an aluminum plate and a stainless-steel plate. Piezoelectric wafer transducer was used to actuate the interrogating Lamb wave. To obtain the scattered waves as well as the incident waves, a scanning laser Doppler vibrometer was adopted for acquiring time-space multidimensional wavefield, followed with frequency-wavenumber processing. The proof-of-concept study was conducted in an aluminum plate with a hairline fatigue crack. A frequency-wavenumber filtering method was used to obtain the incident wave and the scattered wave wavefields for the cross-correlation imaging. After this, the imaging method was applied to evaluate cracks on a stainless-steel plate generated during fatigue loading tests. The presented imaging method showed successful inspection and quantification results of the crack and its growth.

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Experimental Fatigue Crack Propagation Simulation by ANN of a Newly Developed Controlled Rolled Microalloyed Steel Plate

2011 IEEE Electronics, Robotics and Automotive Mechanics Conference ◽

10.1109/cerma.2011.17 ◽

2011 ◽

Author(s):

Jan Mayen ◽

Sergio Serna ◽

Bernardo Campillo ◽

Marco Antonio Cruz Ch´vez ◽

Arturo Molina ◽

...

Keyword(s):

Fatigue Crack ◽

Crack Propagation ◽

Fatigue Crack Propagation ◽

Steel Plate ◽

Microalloyed Steel

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Specimen's Short Fatigue Crack Fabrication Test for Q420qE

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.711.107 ◽

2013 ◽

Vol 711 ◽

pp. 107-109

Author(s):

Qi Ming Yu

Keyword(s):

Fracture Toughness ◽

Fatigue Crack ◽

Steel Plate ◽

Crack Tip ◽

Fatigue Performance ◽

Fracture Toughness Test ◽

Experimental Basis ◽

Bridge Steel ◽

Open Displacement ◽

Text Study

According to the BS7448 fracture toughness test standard, this paper conducted a CTOD(crack tip open displacement) fatigue crack precast test with the bridge steel and analysis the tests results, thus obtained the related conclusions. With the increase of thickness and strength of the steel plate, the security of fatigue performance and toughness of the plate is becoming more important for the structure. So the evaluation of fatigue performance is a very significant work for engineer. This dissertation through the text study the CTOD Specimens Fatigue Crack Prefabricated process of bridge steel and its characteristics, and its results will provide the important experimental basis and computation basis.

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