Quantitative study of electromagnetic wave characteristic values for mortar’s crack

Chang, Che Way; Lin, Chen Hua; Yuan, Qi-Wang

doi:10.1016/j.conbuildmat.2017.09.171

Cited by 3 publications

(3 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The connection between dielectric permittivity and EM wave velocity (v) could be formulated by Equation (1). The variation of two-way travel time, amplitude, or/and frequency of reflection wave are measured by Equation (2) [4].…”

Section: Description Of Radar Wave Transmission and Reflectionmentioning

confidence: 99%

Object Detection of Ground-Penetrating Radar Signals Using Empirical Mode Decomposition and Dynamic Time Warping

Senalik

Wacker

et al. 2020

Forests

View full text Add to dashboard Cite

An object detection method of ground-penetrating radar (GPR) signals using empirical mode decomposition (EMD) and dynamic time warping (DTW) is proposed in this study. Two groups of timber specimens were examined. The first group comprised of Douglas fir (Pseudotsuga menziesii) timber sections prepared in the laboratory with inserts of known internal characteristics. The second group comprised of timber girders salvaged from the timber bridges on historic Route 66 over 80 years. A GSSI Subsurface Interface Radar (SIR) System 4000 with a 2 GHz palm antenna was used to scan these two groups of specimens. GPR sensed differences in dielectric constants (DC) along the scan path caused by the presence of water, metal, or air within the wood. This study focuses on the feature identification and defect classification. The results show that the processing methods were efficient for the illustration of GPR information.

show abstract

Section: Description Of Radar Wave Transmission and Reflectionmentioning

confidence: 99%

Object Detection of Ground-Penetrating Radar Signals Using Empirical Mode Decomposition and Dynamic Time Warping

Senalik

Wacker

et al. 2020

Forests

View full text Add to dashboard Cite

show abstract

“…GPR systems prove to be efficient non-destructive instruments that employ the transmission and reception of electromagnetic waves for detecting targets beneath various surfaces [1]. It finds application in tasks such as characterizing tile breakages, conducting soil surveys, analyzing asphalt structures, and hole discovery in vulnerable areas [2].…”

Section: Introductionmentioning

confidence: 99%

Design and Realization of 2.4 GHz Bowtie Antenna for Ground Penetrating Radar (GPR)

ALtalqi,

Elisa,

Echchelh

2023

IJEEI

View full text Add to dashboard Cite

In this research, a microstrip antenna with a bowtie hole was constructed. The proposed antenna is designed and fabricated to operate in the 2.4 GHz frequency band. Arc antennas are a popular choice due to their flat structure, lightweight design, wide bandwidth, and high gain characteristics for GPR applications. The antenna was designed as a microstrip antenna in the size of 58 mm x 69 mm. using an FR4 duplex printed circuit board with a material thickness of 1.6 mm, a dielectric constant of 4.3 and a transverse dielectric loss tangent of 0.02. The design and simulation were performed using CST Studio Suite programming. The results of the simulation and measurements antenna were tested for resonant frequency, return loss, VSWR, bandwidth, impedance, and polarization, and the simulation results were compared. The measurements carried out with a Vector Network Analyzer, showed a return loss of -18, a VSWR of 1.29, a bandwidth of 100 MHz, an impedance of 47 ohms, and a high gain of 18 dB at 2.42 GHz. Both the simulation and measurement results demonstrated good agreement, with frequency bands of interest that were very close and stable with high-gain omnidirectional radiation characteristics. Thus, the antenna is well-suited to meet the requirements of GPR applications.

show abstract

“…We think that if we can identify the arrangement of iron bars inside a concrete wall and arrange WPT couplers to avoid these bars, the power loss can be reduced. Nondestructive methods for inspecting the inside of concrete structures include the impact-echo method [2,3], reinforced-concrete (RC) radar [4,5], and X-ray transmission [6,7]. Among them, RC radar is most frequently used, but the radio-wave intensity is restricted by radio regulation in Japan, and thus the exploration depth of RC rebar is up to 30 cm [8].…”

Section: Introductionmentioning

confidence: 99%

Locating embedded iron bars for wireless power transmission through reinforced-concrete wall

2019

View full text Add to dashboard Cite

We previously showed that using low-frequency magnetic waves is effective for wireless power transmission (WPT) through reinforced-concrete walls. When a magnetic wave below 400 Hz was used, it was confirmed that the temperature increase of iron objects inside concrete is very small by numerical calculation based on a non-steady heat conduction equation that included a one-dimensional heat conduction term and heat generation term. However, even if the frequency was lowered to 60 Hz, the power loss was still serious due to magnetic coupling impedance caused by iron bars, such as a rebar lattice, inside the concrete wall. This fact was confirmed from both experiments and numerical calculations. In this study, we propose an iron bar location system using a pair of patch antennas to detect iron bars embedded in the concrete and use this information to place WPT couplers away from embedded iron. Then, we show that the proposed system can be adapted to concrete walls up to 70 cm thick by numerical calculation with the finite-difference timedomain method. Our research results will contribute to WPT in cases where iron bars or pipes are present inside a wall.

show abstract

Quantitative study of electromagnetic wave characteristic values for mortar’s crack

Cited by 3 publications

References 15 publications

Object Detection of Ground-Penetrating Radar Signals Using Empirical Mode Decomposition and Dynamic Time Warping

Object Detection of Ground-Penetrating Radar Signals Using Empirical Mode Decomposition and Dynamic Time Warping

Design and Realization of 2.4 GHz Bowtie Antenna for Ground Penetrating Radar (GPR)

Locating embedded iron bars for wireless power transmission through reinforced-concrete wall

Contact Info

Product

Resources

About