This study aims to develop a damage-detection algorithm based on the electromagnetic wave properties inside a reinforced concrete structure.The proposed method involves employing two algorithms based on data measured ...This study aims to develop a damage-detection algorithm based on the electromagnetic wave properties inside a reinforced concrete structure.The proposed method involves employing two algorithms based on data measured using ground-penetrating radar—a common electromagnetic wave method in civil engineering.The possible defect area was identified based on the energy dissipated by the damage in the frequency-wavenumber domain,with the damage localized using the calculated relative permittivity of the measurements.The proposed method was verified through a finite difference time-domain-based numerical analysis and a testing slab with artificial damage.As a result of verification,the proposed method quickly identified the presence of damage inside the concrete,especially for honeycomb-like defects located at the top of the rebar.This study has practical significance in scanning structures over a large area more quickly than other non-destructive testing methods,such as ultrasonic methods.展开更多
This paper introduces recent research work in the field of pulsed electromagnetic non-destructive testing/evaluation.These are pulsed eddy current,pulsed magnetic flux leakage and eddy current pulsed thermography.This...This paper introduces recent research work in the field of pulsed electromagnetic non-destructive testing/evaluation.These are pulsed eddy current,pulsed magnetic flux leakage and eddy current pulsed thermography.This paper introduces pulsed electromagnetic techniques and their different case studies on defect detection as well as stress characterisation.Experimental tests have been validated and future research plans are discussed.This paper demonstrates pulsed electromagnetic non-destructive testing and evaluation for not only depth information,but also for multiple parameter measurement and multiple integration,which are important for future development.展开更多
The feasibility of electromagnetically stimulated thermography non-destructive testing(NDT)for the detection of defects in metallic conductive materials has been carried out by finite element analysis.Aluminum plates ...The feasibility of electromagnetically stimulated thermography non-destructive testing(NDT)for the detection of defects in metallic conductive materials has been carried out by finite element analysis.Aluminum plates with defects of different diameters,depths,locations,shapes and orientation with respect to eddy current are numerically investigated.ANSYS software is used to solve the coupled electromagnetic and temperature field equations.The peak temperatures on the top surface of circular defects with different diameters and depths are calculated at varying excitation frequencies.It is demonstrated that the obtained temperature inreases with increase of the defect diameter and decrease of its depth.The dependence of the temperature over the top surface of the defect on its location and orientation is also presented.The results indicate that we can detect the subsurface defect and estimate its depth and location by choosing a suitable coil-specimen configuration.展开更多
基金National Research Foundation of Korea(NRF)Funded by the Korean Government(MSIT)under Grant Nos.RS-2023-00210317 and 2021R1A4A3030117the Digital-Based Building Construction and Safety Supervision Technology Research Program Funded by the Ministry of Land,Infrastructure,and Transport of the Korean Government under Grant No.RS-2022-00143493the Korea Institute of Civil Engineering and Building Technology(KICT)of the Republic of Korea,Project under Grant No.2023-0097。
文摘This study aims to develop a damage-detection algorithm based on the electromagnetic wave properties inside a reinforced concrete structure.The proposed method involves employing two algorithms based on data measured using ground-penetrating radar—a common electromagnetic wave method in civil engineering.The possible defect area was identified based on the energy dissipated by the damage in the frequency-wavenumber domain,with the damage localized using the calculated relative permittivity of the measurements.The proposed method was verified through a finite difference time-domain-based numerical analysis and a testing slab with artificial damage.As a result of verification,the proposed method quickly identified the presence of damage inside the concrete,especially for honeycomb-like defects located at the top of the rebar.This study has practical significance in scanning structures over a large area more quickly than other non-destructive testing methods,such as ultrasonic methods.
基金Sichuan province Science and Technology department( No. 2011GZ0002 and No. 2013HH0059)the university basic scientific research project( No. ZYGX2013J090 ) for funding the work
文摘This paper introduces recent research work in the field of pulsed electromagnetic non-destructive testing/evaluation.These are pulsed eddy current,pulsed magnetic flux leakage and eddy current pulsed thermography.This paper introduces pulsed electromagnetic techniques and their different case studies on defect detection as well as stress characterisation.Experimental tests have been validated and future research plans are discussed.This paper demonstrates pulsed electromagnetic non-destructive testing and evaluation for not only depth information,but also for multiple parameter measurement and multiple integration,which are important for future development.
基金the National Natural Science Foundation of China(No.51075388)the Fundamental Research Funds for the Central Universities (No.2009KJ05)
文摘The feasibility of electromagnetically stimulated thermography non-destructive testing(NDT)for the detection of defects in metallic conductive materials has been carried out by finite element analysis.Aluminum plates with defects of different diameters,depths,locations,shapes and orientation with respect to eddy current are numerically investigated.ANSYS software is used to solve the coupled electromagnetic and temperature field equations.The peak temperatures on the top surface of circular defects with different diameters and depths are calculated at varying excitation frequencies.It is demonstrated that the obtained temperature inreases with increase of the defect diameter and decrease of its depth.The dependence of the temperature over the top surface of the defect on its location and orientation is also presented.The results indicate that we can detect the subsurface defect and estimate its depth and location by choosing a suitable coil-specimen configuration.
