In situ measurements of hot-mix asphalt dielectric properties

Al-Qadi, Imad L.; Lahouar, Samer; Loulizi, Amara

doi:10.1016/s0963-8695(01)00010-x

Cited by 50 publications

(24 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The GPR was placed on a large metal plate and switched to work. In this case, the amplitude of reflected signal could be considered as the amplitude of the incident signal, and then the dielectric constant could be obtained [33]. According to the calculated dielectric constant, the velocity of the electromagnetic wave propagation through the n th layer of pavement was determined as:

v_{n} = \frac{true}{c}

where, c is the speed of light in vacuum,

ε_{r, n}

is the dielectric constant of n th layer.…”

Section: Instruments and Methodsmentioning

confidence: 99%

Rapid Detection Methods for Asphalt Pavement Thicknesses and Defects by a Vehicle-Mounted Ground Penetrating Radar (GPR) System

Dong

Gao

et al. 2016

Sensors

View full text Add to dashboard Cite

The thickness estimation of the top surface layer and surface layer, as well as the detection of road defects, are of great importance to the quality conditions of asphalt pavement. Although ground penetrating radar (GPR) methods have been widely used in non-destructive detection of pavements, the thickness estimation of the thin top surface layer is still a difficult problem due to the limitations of GPR resolution and the similar permittivity of asphalt sub-layers. Besides, the detection of some road defects, including inadequate compaction and delamination at interfaces, require further practical study. In this paper, a newly-developed vehicle-mounted GPR detection system is introduced. We used a horizontal high-pass filter and a modified layer localization method to extract the underground layers. Besides, according to lab experiments and simulation analysis, we proposed theoretical methods for detecting the degree of compaction and delamination at the interface, respectively. Moreover, a field test was carried out and the estimated results showed a satisfactory accuracy of the system and methods.

show abstract

v_{n} = \frac{true}{c}

where, c is the speed of light in vacuum,

ε_{r, n}

is the dielectric constant of n th layer.…”

Section: Instruments and Methodsmentioning

confidence: 99%

Rapid Detection Methods for Asphalt Pavement Thicknesses and Defects by a Vehicle-Mounted Ground Penetrating Radar (GPR) System

Dong

Gao

et al. 2016

Sensors

View full text Add to dashboard Cite

show abstract

“…reported an average error of between 5% and 10%, depending on the dielectric constant estimation technique utilized Al-Qadi et al (2001). conducted GPR surveys on a test section of Route 288 in Richmond, Virginia, to evaluate the performance of the GPR when it was used as a QA-QC tool for a newly built pavement system.…”

mentioning

confidence: 99%

In-Place Hot-Mix Asphalt Density Estimation Using Ground-Penetrating Radar

Al-Qadi

Leng

Lahouar

et al. 2010

Transportation Research Record

View full text Add to dashboard Cite

In-situ asphalt mixture density is critically important to the performance of flexible airport pavements: density that is too high, or too low, may cause early pavement distresses.Traditionally, two methods have been commonly used for in-situ asphalt mixture density measurement: laboratory testing on field-extracted cores and in-situ nuclear gauge testing.However, both these methods have limitations. The coring method damages pavement, causes traffic interruption, and provides only limited data at discrete locations. The nuclear gauge method also provides limited data measurement. Moreover, it requires a license for the operators because it uses radioactive material. To overcome the limitations of these traditional methods, this study proposes to develop a nondestructive method of using ground penetrating radar (GPR) to measure in-situ asphalt mixture density accurately, continuously, and rapidly.The prediction of asphalt mixture density using GPR is based on the fact that the dielectric constant of an asphalt mixture, which can be measured by GPR, is dependent on the dielectric and volumetric properties of its components. According to electromagnetic (EM) mixing theory, two candidate specific gravity models, namely the modified complex refractive index model (CRIM) and the modified Bottcher model, were developed to predict the bulk specific gravity of asphalt mixture from its dielectric constant.To evaluate the performance of these two models, a full-scale six-lane test site with four sections in each lane was carefully designed and constructed. Forty cores were extracted from the test site, and their densities were measured in the laboratory and compared to the GPRpredicted values using the two models. Both models were found effective in predicting asphalt mixture density, although the modified Bottcher model performed better. To account for the effect of the non-spherical inclusions in asphalt mixture and further improve the density prediction accuracy, a shape factor was introduced into the modified Bottcher model. Nonlinear least square curve fitting of the field core data indicated that a shape factor of -0.3 provided the best-performance model, which is referred to as the Al-Qadi Lahouar Leng (ALL) model.The performance of the ALL model was validated using data collected from an active pavement construction site in Chicago area. It was found that when the ALL model was employed, the prediction accuracy of the GPR was comparable to, or better than, that of the traditional nuclear gauge. For the asphalt mixtures without slags, the average density prediction errors of GPR were between 0.5% and 1.1% with two calibration cores, while those of the nuclear gauge were between 1.2% and 3.1%. iv Due to the importance of accurate input of the dielectric constant of asphalt mixture to the prediction accuracy of the specific gravity model, this study also looked into alternative methods for asphalt mixture dielectric constant estimation. The extended common mid-point (XCMP) method using two air-coupled antenna systems ...

show abstract

“…The effective, bulk dielectric properties of composite materials are determined by dielectric properties of its components. Different mixing formulas in respect of asphalt are studied (Al-Qadi et al, 2001;Leng, 2011;Leng et al, 2011). One of the simplest ones Eq.…”

Section: Asphalt Pavement Homogeneitymentioning

confidence: 99%

Representative volume element of asphalt pavement for electromagnetic measurements

Pellinen

Huuskonen-Snicker

Eskelinen

et al. 2015

Journal of Traffic and Transportation Engineering (English Edit

View full text Add to dashboard Cite

a b s t r a c tThe motivation for this study was to investigate the representative volume element (RVE) needed to correlate the nondestructive electromagnetic (EM) measurements with the conventional destructive asphalt pavement quality control measurements. A large pavement rehabilitation contract was used as the test site for the experiment. Pavement cores were drilled from the same locations where the stationary and continuous Ground Penetrating Radar (GPR) measurements were obtained. Laboratory measurements included testing the bulk density of cores using two methods, the surface-saturated dry method and determining bulk density by dimensions. Also, Vector Network Analyzer (VNA) and the through specimen transmission configuration were employed at microwave frequencies to measure the reference dielectric constant of cores using two different footprint areas and therefore volume elements. The RVE for EM measurements turns out to be frequency dependent; therefore in addition to being dependent on asphalt mixture type and method of obtaining bulk density, it is dependent on the resolution of the EM method used. Then, although the average bulk property results agreed with theoretical formulations of higher core air void content giving a lower dielectric constant, for the individual cores there was no correlation for the VNA measurements because the volume element seizes deviated.Similarly, GPR technique was unable to capture the spatial variation of pavement air voids measured from the 150-mm drill cores. More research is needed to determine the usable RVE for asphalt. © 2015 Periodical Offices of Chang'an University. Production and hosting by Elsevier B.V. on behalf of Owner. This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/).

show abstract

In situ measurements of hot-mix asphalt dielectric properties

Cited by 50 publications

References 1 publication

Rapid Detection Methods for Asphalt Pavement Thicknesses and Defects by a Vehicle-Mounted Ground Penetrating Radar (GPR) System

Rapid Detection Methods for Asphalt Pavement Thicknesses and Defects by a Vehicle-Mounted Ground Penetrating Radar (GPR) System

In-Place Hot-Mix Asphalt Density Estimation Using Ground-Penetrating Radar

Representative volume element of asphalt pavement for electromagnetic measurements

Contact Info

Product

Resources

About