2011 Fiscal Year Final Research Report

Development of a monitoring method for fatigue damage using piezoelectric element

Research Project

Project/Area Number	21560840
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	Naval and maritime engineering
Research Institution	National Maritime Research Institute
Principal Investigator	NIWA Toshio 独立行政法人海上技術安全研究所, 構造系, 上席研究員 (10208267)
Co-Investigator(Kenkyū-buntansha)	SHIMADA Michio (独)海上技術安全研究所, 構造系, 上席研究員 (30396246) TANAKA Yashihisa (独)海上技術安全研究所, 構造系, 主任研究員 (70399517)
Project Period (FY)	2009 – 2011
Keywords	船舶検査 / モニタリング / 超音波 / 疲労き裂 / 応力 / 隅肉溶接
Research Abstract	This paper describes a development of ultrasonic monitoring technique applied for through thickness fatigue cracks neighboring fillet weld parts. A combination of transmitted wave measurement and reflected wave measurement was found to be useful in quantitative detection of the fatigue crack. In case of 100mm separation between transmitting probe and receiving probe, our method obtains 40mm as an effective area for the quantitative detection. In other hand, fatigue crack bring about an underestimation of the cracks under lower stress amplitude. Therefore, it is important for a timing optimization of data acquisition by a synchronization with ship movement.

(1 results)