Detecting Stripping in Asphalt Concrete Layers Using Ground Penetrating Radar

1997 ◽  
Vol 1568 (1) ◽  
pp. 165-174 ◽  
Author(s):  
Elias Rmeili ◽  
Tom Scullion
Keyword(s):  
Ground Penetrating Radar ◽  
Ground Truth ◽  
Department Of Transportation ◽  
Portland Cement Concrete ◽  
Design Decisions ◽  
Texas Department ◽  
1960S And 1970S ◽  
The 1960S ◽  
Ground Penetrating ◽  
Asphalt Overlays

A study undertaken by the Texas Department of Transportation to nondestructively detect stripping in the asphalt surfacing on I-45 in the Bryan district is described. The highway was constructed in the 1960s and 1970s with an initial portland cement concrete thickness of 200 mm. Since then, several asphalt overlays have been applied. Maintenance of this highway is a recurring problem, and it is known that in several locations moderate to severe areas of subsurface stripping are present. To plan the future rehabilitation of this important highway, the Bryan district investigated the ability of ground penetrating radar (GPR) to provide subsurface condition information. A GPR survey was conducted at close to highway speeds, and the data were interpreted before taking validation cores. The GPR was used to provide information concerning the section breaks along the highway on the basis of asphalt layer thickness and condition, the average thickness of the asphalt layer within each section, and the extent and severity of any defect in the asphalt layer. More than 60 cores were taken to correlate the GPR interpretation. GPR results and ground truth cores are compared. In general, the comparisons were good. The GPR equipment and interpretation schemes used were found to provide information of sufficient quality and accuracy to permit the district to make programming decisions. GPR is now being used on several additional projects in the Bryan district. The best use appears to be for both defect detection and thickness estimation before deflection testing and coring. GPR will not eliminate coring or deflection testing, but by using all three in a coordinated approach pavement designers will have more confidence in their design decisions.

Application of Infrared Imaging and Ground-Penetrating Radar to Detect Segregation in Hot-Mix Asphalt Overlays

2003 ◽  
Vol 1861 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Stephen Sebesta ◽  
Tom Scullion
Keyword(s):  
Ground Penetrating Radar ◽  
Infrared Imaging ◽  
Hot Mix Asphalt ◽  
Poor Performance ◽  
Radar Data ◽  
Engineering Properties ◽  
Void Content ◽  
Graded Materials ◽  
Texas Department ◽  
Ground Penetrating

Segregation is a serious problem in hot-mix asphalt and typically results in poor performance, poor durability, a shorter life, and higher maintenance costs for the pavement. A summary of the results and recommendations from three projects in Texas in which infrared imaging and ground-penetrating radar were used to examine the uniformity of the pavement mat is presented. Both techniques have significant advantages over currently used nuclear density techniques in that they provide virtually 100% coverage of the new surface. The effectiveness of both the infrared and radar techniques was evaluated by taking measurements on new overlays at the time of placement, coring, and then identifying relationships between changes in the infrared and radar data with changes in the measured volumetric and engineering properties of the cores. Analyses of the results showed that changes in both infrared and radar data are significantly related to changes in hot-mix asphalt properties such as air void content and gradation. On the basis of current Texas Department of Transportation specifications, significant changes in the hot-mix asphalt are expected if temperature differentials of greater than 25°F (13.9°C) are measured after placement but before rolling. If the surface dielectric of the in-place mat changes by more than 0.8 for coarse-graded mixes and 0.4 for dense-graded materials, significant changes in mix properties are expected. Given the promising results from this work, agencies should consider implementing both the infrared and ground-penetrating radar technologies.

Predicting material properties of concrete from ground-penetrating radar attributes

2020 ◽  
pp. 147592172097699
Author(s):  
Isabel M Morris ◽  
Vivek Kumar ◽  
Branko Glisic
Keyword(s):  
Compressive Strength ◽  
Physical Properties ◽  
Ground Penetrating Radar ◽  
Material Properties ◽  
Regression Models ◽  
Physical Property ◽  
Portland Cement Concrete ◽  
Instantaneous Amplitude ◽  
Data Set ◽  
Ground Penetrating

We present here a laboratory-based experimental protocol that seeks to establish and characterize the relationship between ground-penetrating radar attributes and the mechanical properties (density, porosity, and compressive strength) of typical industry concrete mixes. The experimental data consist of ground-penetrating radar attributes from 900 MHz radargrams that correspond to simultaneously measured physical properties of Portland cement concrete, alkali-activated concrete, and cement mortar. Appropriate regression models are trained and tested on this data set to predict each physical property from ground-penetrating radar attributes. From a small selection of individual attributes, including total phase and intensity, trained random forest regression models predict porosity ( R2 = 0.83 from the instantaneous amplitude), density ( R2 = 0.67 from the intensity attribute), and compressive strength ( R2 = 0.51 from instantaneous amplitude). These novel relationships between physical properties and ground-penetrating radar attributes indicate that material properties could be predicted from the attributes of ordinary ground-penetrating radar scans of concrete.

Ground-Penetrating Radar, Chain Drag, and Ground Truth

2008 ◽  
Vol 2044 (1) ◽  
pp. 39-50 ◽  
Author(s):  
Sherif Yehia ◽  
Osama Abudayyeh ◽  
Ikhlas Abdel-Qader ◽  
Ammar Zalt
Keyword(s):  
Ground Penetrating Radar ◽  
Ground Truth ◽  
Ground Penetrating

Ground-penetrating radar data diffraction focusing without a velocity model

Geophysics ◽  
2020 ◽  
Vol 85 (3) ◽  
pp. H13-H24
Author(s):  
Nikos Economou ◽  
Antonis Vafidis ◽  
Maksim Bano ◽  
Hamdan Hamdan ◽  
Jose Ortega-Ramirez
Keyword(s):  
Ground Penetrating Radar ◽  
Constant Velocity ◽  
Electromagnetic Waves ◽  
Ground Truth ◽  
Velocity Model ◽  
Migration Velocity ◽  
Dominant Frequency ◽  
Limited Information ◽  
Velocity Range ◽  
Ground Penetrating

Ground-penetrating Radar (GPR) sections commonly suffer from strong scattered energy and weak reflectors with distorted lateral continuity. This is mainly due to the gradual variation of moisture with depth, dense lateral sampling of common-offset GPR traces (which are considered as zero-offset data), along with the small wavelength of the electromagnetic waves that is comparable to the size of the shallow subsurface dielectric heterogeneities. Focusing of the diffractions requires efficient migration that, in the presence of highly heterogeneous subsurface formations, can be improved by a detailed migration velocity model. Such a velocity model is difficult to develop because the common-offset antenna array is mostly used for its reduced time and cost in the data acquisition and processing stages. In such cases, migration processes are based on limited information from velocity analysis of clear diffractions, cores, or other ground truth knowledge, often leading to insufficient imaging. We have developed a methodology to obtain GPR sections with focused diffractions that is based on multipath summation, using weighted stacking (summation) of constant-velocity migrated sections over a predefined velocity range. The success of this method depends on the assignment of an appropriate weight, for each constant-velocity migrated section to contribute to the final stack, and the optimal width of the velocity range used. Additionally, we develop a postmultipath summation processing step, which consists of time-varying spectral whitening, to deal with the decrease of the dominant frequency due to attenuation effects and the additional degraded resolution expected by the constant migration summed images. This imaging strategy leads to GPR sections with sufficiently focused diffractions, enhancing the lateral and the temporal resolution, without the need to explicitly build a migration velocity model.

scholarly journals The Fortress Beneath: Ground Penetrating Radar Imaging of the Citadel at Alcatraz: 1. A Guide for Interpretation

Heritage ◽  
2021 ◽  
Vol 4 (3) ◽  
pp. 1328-1347
Author(s):  
Mark E. Everett ◽  
Timothy S. DeSmet ◽  
Robert R. Warden ◽  
Henry A. Ruiz-Guzman ◽  
Peter Gavette ◽  
...  
Keyword(s):  
Cultural Heritage ◽  
Ground Penetrating Radar ◽  
Ground Truth ◽  
Companion Paper ◽  
Evaluation Tool ◽  
Facies Classification ◽  
Central Interest ◽  
Advanced Analysis ◽  
Ground Penetrating ◽  
The 19Th Century

Ground-penetrating radar has emerged as a prominent non-destructive evaluation tool for the study of inaccessible subsurface elements of cultural heritage structures. Often of central interest is the desire to image the remains of a pre-existing historic structure that is located directly beneath a more recently built one. The interpretation of GPR images in such cases is usually difficult due to ambiguities caused by the presence of pervasive clutter, environmental noise, and overlapping target signatures. Sites with abundant ground truth allow for more confident interpretations and serve as a useful testbed to assist similar studies at other places, where little or no ground truth is available. This study reports GPR interpretations of structures belonging to the 19th century Citadel beneath the main prison cellhouse at Alcatraz. At this site, lidar scans, direct observations, and historical documents are available to facilitate identification of radar target signatures. A general interpretation of the acquired radargrams is made in this paper, while the companion paper presents more advanced analysis of target signatures based on curvelet image processing. This study points to the development of a radar facies classification scheme that is specific to cultural heritage investigations.

scholarly journals Practical Approach for High-Resolution Airport Pavement Inspection with the Yakumo Multistatic Array Ground-Penetrating Radar System

Sensors ◽  
2018 ◽  
Vol 18 (8) ◽  
pp. 2684 ◽  
Author(s):  
Li Yi ◽  
Lilong Zou ◽  
Motoyuki Sato
Keyword(s):  
Ground Penetrating Radar ◽  
Estimation Method ◽  
Ground Truth ◽  
Radar System ◽  
Velocity Estimation ◽  
Velocity Spectrum ◽  
Airport Pavement ◽  
Ground Penetrating ◽  
Airport Site ◽  
Good Agreement

It is important to identify the thin cracks within the airport pavement layers. To achieve this goal, a practical interferometric approach using the Yakumo multistatic ground-penetrating radar system was developed to detect the slight variability in wave propagation velocity and/or thickness caused by the thin cracks. In comparison with the conventional common midpoint (CMP) velocity estimation method, the proposed method can provide much higher-resolution estimations of slight deviations in the velocity and thickness from their corresponding reference values in the undamaged asphalt through the comparison of two CMP datasets. These deviations can be obtained analytically instead of graphically extracted from the CMP velocity spectrum. The proposed approach was not only analyzed using the simulated datasets, but also practically demonstrated at both an experimental model site and an actual airport site. In the simulation tests, velocity deviations on the order of a few millimeters per nanosecond were detected, and the experimental results shows good agreement with the ground truth and coring samples. This method provides a novel way to inspect partially damaged pavement when the thin cracks are difficult to detect using the reflected signals.

scholarly journals Four-Dimensional Investigation of Gravel Beach Ridge Accretion and 50 Years of Beach Recharge at Dungeness, UK, Using Historic Images, GPR and Lidar (HIGL)

2021 ◽  
Vol 11 (21) ◽  
pp. 10219
Author(s):  
Charlie S. Bristow ◽  
Lucy Buck ◽  
Maria Inggrid
Keyword(s):  
Ground Penetrating Radar ◽  
Nuclear Power ◽  
Aerial Images ◽  
Beach Ridges ◽  
The Past ◽  
Power Stations ◽  
Longshore Drift ◽  
Elevation Data ◽  
The 1960S ◽  
Ground Penetrating

Dungeness is a cuspate foreland on the south coast of England that is the largest shingle feature in Europe and includes hundreds of beach ridges. It is also the location of two nuclear power stations that were constructed in the 1960s. The dominant southwest waves cause longshore drift from west to east, eroding the southwest side of Dungeness, accompanied by accretion on the east side. A record of this eastward movement and sediment accretion is preserved by the shingle beach ridges. The power stations are located on the eroding southwestern side of the ness, and a system of beach recharge has been used to move shingle from the downdrift, east-facing shore to the updrift, southwest-facing shore to protect the power stations from coastal erosion. We use a novel combination of historic images, ground-penetrating radar (GPR), and Lidar (HIGL) to investigate accretion and beach ridges at Dungeness during the past 80 years. We report changes in accretion along the coast and use GPR to determine the thickness of beach gravels. The amount of accretion, represented by the width of the backshore, decreases downdrift from south to north. The number of beach ridges preserved also decreases from south to north. By combining the shingle thickness from GPR with elevation data from Lidar surveys and records of beach accretion measured from aerial images, we estimate the volume and mass of gravel that has accumulated at Dungeness. Historic rates of beach accretion are similar to recent rates, suggesting that the 55 years of beach recharge have had little impact on the longer-term accretion downdrift.

REFLECTION COEFFICIENT OF AN ELECTROMAGNETIC WAVE IN CONDUCTIVE MEDIA

2018 ◽  
pp. 100-106
Author(s):  
M. S. Sudakova ◽  
M. L. Vladov ◽  
M. R. Sadurtdinov
Keyword(s):  
Reflection Coefficient ◽  
Ground Penetrating Radar ◽  
Electromagnetic Waves ◽  
Water Contamination ◽  
Survey Design ◽  
Direct And Inverse Problems ◽  
The Difference ◽  
Ground Penetrating ◽  
Ideal Dielectric

Within the ground penetrating radar bandwidth the medium is considered to be an ideal dielectric, which is not always true. Electromagnetic waves reflection coefficient conductivity dependence showed a significant role of the difference in conductivity in reflection strength. It was confirmed by physical modeling. Conductivity of geological media should be taken into account when solving direct and inverse problems, survey design planning, etc. Ground penetrating radar can be used to solve the problem of mapping of halocline or determine water contamination.

Ken Russell's Wartime Imagery

2015 ◽  
Vol 12 (4) ◽  
pp. 539-555 ◽  
Author(s):  
Kevin M. Flanagan
Keyword(s):  
Second World War ◽  
World War ◽  
War Films ◽  
Personal Style ◽  
American Cinema ◽  
1960S And 1970S ◽  
The 1960S ◽  
Second World ◽  
Wartime Experience ◽  
National Experience

This article traces Ken Russell's explorations of war and wartime experience over the course of his career. In particular, it argues that Russell's scattered attempts at coming to terms with war, the rise of fascism and memorialisation are best understood in terms of a combination of Russell's own tastes and personal style, wider stylistic and thematic trends in Euro-American cinema during the 1960s and 1970s, and discourses of collective national experience. In addition to identifying Russell's recurrent techniques, this article focuses on how the residual impacts of the First and Second World Wars appear in his favoured genres: literary adaptations and composer biopics. Although the article looks for patterns and similarities in Russell's war output, it differentiates between his First and Second World War films by indicating how he engages with, and temporarily inhabits, the stylistic regime of the enemy within the latter group.

Mind Bending, Mental Seduction and Menticide: Brainwashing in British Spy Dramas of the 1960s

2013 ◽  
Vol 10 (1) ◽  
pp. 27-48 ◽  
Author(s):  
Alan Burton
Keyword(s):  
Cold War ◽  
Thought Control ◽  
Cultural Contexts ◽  
Scientific Background ◽  
Mind Control ◽  
1960S And 1970S ◽  
The 1960S ◽  
The Cold War ◽  
The Mind ◽  
Cultural Fantasy

Brainwashing assumed the proportions of a cultural fantasy during the Cold War period. The article examines the various political, scientific and cultural contexts of brainwashing, and proceeds to a consideration of the place of mind control in British spy dramas made for cinema and television in the 1960s and 1970s. Particular attention is given to the films The Mind Benders (1963) and The Ipcress File (1965), and to the television dramas Man in a Suitcase (1967–8), The Prisoner (1967–8) and Callan (1967–81), which gave expression to the anxieties surrounding thought-control. Attention is given to the scientific background to the representations of brainwashing, and the significance of spy scandals, treasons and treacheries as a distinct context to the appearance of brainwashing on British screens.

Sign in / Sign up

Export Citation Format

Share Document