Nonlinear ultrasonic guided waves for stress monitoring in prestressing tendons for post-tensioned concrete structures

2009 ◽  
Author(s):  
Ivan Bartoli ◽  
Claudio Nucera ◽  
Ankit Srivastava ◽  
Salvatore Salamone ◽  
Robert Phillips ◽  
...  
Keyword(s):  
Guided Waves ◽  
Concrete Structures ◽  
Ultrasonic Guided Waves ◽  
Stress Monitoring ◽  
Nonlinear Ultrasonic ◽  
Post Tensioned

Delamination Detection in Composite Plates Using Linear and Nonlinear Ultrasonic Guided Waves

2019 ◽  
Author(s):  
Yanfeng Shen ◽  
Mingjing Cen
Keyword(s):  
Wave Propagation ◽  
Guided Waves ◽  
Fiber Composite ◽  
Composite Plates ◽  
Ultrasonic Guided Waves ◽  
Carbon Fiber Composite ◽  
Laser Doppler Vibrometry ◽  
Delamination Detection ◽  
Nonlinear Ultrasonic ◽  
Linear And Nonlinear

Abstract This paper presents a delamination detection strategy for composite plates using linear and nonlinear ultrasonic guided waves via the wave field imaging and signal processing based on Scanning Laser Doppler Vibrometry (SLDV). The anisotropic elastodynamics in composite plates is first studied. Two numerical methods are deployed to analyze the wave mechanics within the composite plates. The Semi-analytical Finite Element (SAFE) method is utilized to obtain the dispersion curves and mode shapes for a carbon fiber composite plate by bonding two quasi-isotropic carbon fiber composite panels together. The Local Interaction Simulation Approach has been employed to investigate the wave propagation and interaction with the delamination. Contact Acoustic Nonlinearity (CAN) between the delamination interfaces during wave damage interaction is presented as a potential mechanism for delamination detection. After developing an in-depth understanding of the wave propagation and wave damage interaction mechanism, active sensing experiments are conducted using the Piezoelectric Wafer Active Sensors (PWAS) and the Scanning Laser Doppler Vibrometry (SLDV). Two delamination imaging methodologies are presented. The first one utilizes the total wave energy to detect the delamination, taking advantage of the trapped modes within the delaminated area. The second one adopts the nonlinear second harmonic imaging algorithm, highlighting the nonlinear interaction traces at the delamination region. The damage detection images are finally compared and fused to provide detailed diagnostic information of the delamination. The damage imaging technique presented in this paper possesses great potential in material evaluation and characterization applications. This paper finishes with summary, concluding remarks, and suggestions for future work.

Ultrasonic guided waves for monitoring corrosion of FRP wrapped concrete structures

2015 ◽  
Vol 96 ◽  
pp. 690-702 ◽  
Author(s):  
Ashutosh Sharma ◽  
Shruti Sharma ◽  
Sandeep Sharma ◽  
Abhijit Mukherjee
Keyword(s):  
Guided Waves ◽  
Concrete Structures ◽  
Ultrasonic Guided Waves

scholarly journals Defects Inspection in Wires by Nonlinear Ultrasonic-Guided Wave Generated by Electromagnetic Sensors

2020 ◽  
Vol 10 (13) ◽  
pp. 4479
Author(s):  
Junpil Park ◽  
Jaesun Lee ◽  
Junki Min ◽  
Younho Cho
Keyword(s):  
Guided Waves ◽  
Raw Materials ◽  
Effective Means ◽  
Guided Wave ◽  
Ultrasonic Guided Waves ◽  
Electromagnetic Acoustic Transducer ◽  
Safety Issues ◽  
Steel Wires ◽  
Nonlinear Ultrasonic ◽  
Principles Of Design

Steel wires are widely used as raw materials for spring valves in engines. Considering the quality and safety issues of their structure, there is a demand to develop nondestructive inspection approaches to detect initial damages in steel. In this study, nonlinear ultrasonic-guided waves generated by an electromagnetic acoustic transducer (EMAT) were used to inspect the defects in steel wires. As one of the noncontact testing methods, the use of EMAT has significant advantages to decrease the nonlinearity induced by instruments and transducer contact condition. The principles of design and manufacturing of EMAT are first introduced. The fundamental theory of nonlinear guided waves is also briefly discussed in this investigation. Phase-matched guided wave modes were generated and measured by using EMAT. Variations of acoustic nonlinearity corresponding to existing defects in specimens were obtained. A scanning electron microscope (SEM) was used to check the existence of microdefects in specimen. The results indicate that the use of EMAT can be an effective means to generate and measure nonlinear ultrasonic-guided waves for inspection of microdefects.

Sign in / Sign up

Export Citation Format

Share Document