The Experts below are selected from a list of 2277 Experts worldwide ranked by ideXlab platform
Douglas D. Gransberg - One of the best experts on this subject based on the ideXlab platform.
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Chip Seal aggregate evaluation and successful roads preservation
Construction and Building Materials, 2018Co-Authors: Ashley Buss, Minas Guirguis, Douglas D. GransbergAbstract:Abstract The Federal Highway Administration’s Every Day Counts (EDC) initiative focuses on saving time, resources and money. EDC has brought infrastructure preservation to the forefront of many conversations. Chip Seals are a cost-effective pavement preservation strategy, and continued studies verifying their performance benefits continue to be in high demand as agencies struggle to fund preservation programs. This study documents the effectiveness of Chip Seals when good materials, good construction and good agency oversight work together. Chips Seals extend the service life of pavements an average of 5–6 years. This study gathers two years of field performance data (June 2014–June 2016) from Chip Seal projects constructed in Oregon. The data includes laboratory and field-testing to assess Chip Seal materials used in construction and tracks the performance of the Chip Seal pavements, both emulsified asphalts and hot-applied asphalts. Findings show that Chip Seals constructed with good quality materials enhance the surface texture properties and reduce the appearance of distresses over the two-year monitoring period for most sections.
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develop draft Chip Seal cover aggregate specification based on aims angularity shape and texture test results
2013Co-Authors: Musharraf Zaman, Douglas D. Gransberg, Rifat Bulut, Sesh Commuri, Dominique PittengerAbstract:The objective of the study is to improve Oklahoma Department of Transportation (ODOT) Chip Seal design and performance through introducing new criteria for the selection of cover aggregate and binder. These criteria will be based upon the recent technological advances in the characterization of aggregate shape and texture as well as aggregate-binder compatibility. The study evaluates the shape and texture-related index properties, as well as durability, of commonly used cover aggregates in Chip Seal programs in Oklahoma. Additionally, it will provide a methodology for inclusion of these characteristics as a metric in future Chip Seal specifications. The study includes both laboratory testing and construction and performance evaluation of Chip Seal test sections. The study is ongoing and is quantifying how well the newly developed performance-based uniformity coefficient (PUC) correlate with Chip Seal performance in Oklahoma, and if it should be incorporated into state Chip Seal specifications. It has generated aggregate-binder compatibility data, based on the surface free energy (compatibility ratio) approach, for commonly used aggregates and asphalt emulsion binders in Oklahoma. Moreover, the Chip Seal construction practice followed by different ODOT Maintenance Divisions was documented and the best practice identified. This repository of information will be a useful resource for ODOT maintenance divisions.
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performance analysis of aggregate binder combinations used for the odot Chip Seal program
2010Co-Authors: Douglas D. Gransberg, Musharraf Zaman, Bekir AktaşAbstract:This project compared the results of laboratory characterization of Chip Seal aggregate samples for Oklahoma DOT Divisions 1,2,3,5 and 6 with performance data from the Pavement Management System (PMS) database. Binder evaluation was limited to identifying the binder sources associated with each test section and analyzing its performance based on the PMS data. No trend was found from the PMS analysis of binder sources. The laboratory testing consisted of sieve analysis, Los Angeles Abrasion Testing, Micro-Deval Testing, and the use of the Aggregate Imaging System (AIMS) to quantify Chip Seal aggregate characteristics from each division. The output from the laboratory testing was compared with the PMS performance data using linear regression techniques to identify those combinations that displayed a discernable trend. The project’s sample size was small and therefore, the researchers were unable to reach authoritative conclusions. Nevertheless, the analysis found a potential relationship between the LA test and PMS skid number (SN) data. It also identified trends with respect to the AIMS output, particularly between gradient angularity and SN. The Performance-based Uniformity Coefficient introduced by the North Carolina DOT was also evaluated and found to be a promising metric that may warrant future inclusion in the ODOT Chip Seal aggregate specifications.
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Chip Seal Best Practices Pay Off for End Users
2010Co-Authors: Douglas D. Gransberg, Steven MuellerAbstract:In 2005, a survey was conducted of highway agencies that use Chip Seals as part of their pavement preservation programs. The survey was used to identify best practices in Chip Seal design and construction. This article summarizes some of the key best practices identified in this study. Agencies that have achieved excellence use Chip Seals as an active preventive measure. They treat the technology as a science and use formal design procedures that are adjusted based on past experience. The successful agencies also transfer a high degree of specificity from their design process to their construction contracts and in-house maintenance procedures. Once a Chip Seal is applied, they maintain the asphalt membrane by routine crack and fog Sealing. The goal of these agencies is to replicate success rather than simply try to avoid failure.
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using a new zealand performance specification to evaluate u s Chip Seal performance
Journal of Transportation Engineering-asce, 2007Co-Authors: Douglas D. GransbergAbstract:This paper reports the results of a Chip Seal research project in Texas where the researchers are using both quantitative and qualitative means to evaluate Chip Seal performance on rural roads. The team is making specific use of the Transit New Zealand (TNZ) T/3 “sand circle” test to measure the change in average texture depth over time and applying those measurements to the TNZ P/17 performance specification for allowable surface texture deterioration over the first year of Chip Seal performance. The results demonstrate the value of quantitatively characterizing the preSeal surface condition as a benchmark against which to compare new Chip Seal performance. Those roads that had poor preSeal surface conditions as exhibited by low macrotexture as measured by the T/3 sand circle test showed early loss of macrotexture and premature flushing after a new Seal had been applied and failed the specified P/17 1-year texture loss performance criteria. Thus, the paper concludes that not only is having a quantitative metric essential to be able to accurately assess the performance of new Seals but also that the use of the TNZ T/3 sand circle test furnishes an easy, cost-effective means to quantitatively characterize preSeal surface texture.
Bekir Aktaş - One of the best experts on this subject based on the ideXlab platform.
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Laboratory and In Situ Investigation of Chip Seal Surface Condition Improvement
Journal of Performance of Constructed Facilities, 2015Co-Authors: Mustafa Karaşahin, Bekir Aktaş, A. G. Gungor, F. Orhan, Cahit GürerAbstract:This study focuses on determining the effect of different types of binder and aggregate on Chip Seal performance in both laboratory and in situ settings. Eight different Chip Seal test sections were constructed on existing asphalt concrete as the pavement preservation technique of choice. Two different binders, CRS-2L modified emulsion and B100/150 penetration hot asphalt cement, were used in the test sections. Also, two types of aggregate, limestone, and basalt, were used. The sand-patch test as well as visual evaluations was conducted on the test sections regularly. In addition to physical and chemical characteristics, the adhesion resistance of the utilized materials was determined in the laboratory and compared with the test section results. The loss of aggregate (also called raveling or shelling), bleeding deteriorations on each test section were evaluated over time in respect to binder and aggregate type. The results indicate that after Chip Seal construction, the macrotexture of the existing asphalt concrete increased significantly. It was also determined that CRS-2L Chip Seal showed better performance than B100/150 penetration hot asphalt cement. With regard to the type of aggregate used for the Chip Seal, limestone showed better raveling performance when compared with basalt. In addition, in the test sections, the right and left lanes demonstrated different levels of severity distress because of varying traffic distributions. It was also seen that macrotexture is one of the best parameters to determine Chip Seal performance and to follow its progress over time.
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Chip Seal Adhesion Performance with Modified Binder in Cold Climates: Experimental Investigation
Transportation Research Record, 2013Co-Authors: Bekir Aktaş, Mustafa KaraşahinAbstract:The purpose of this study was to evaluate Chip Seal performance with neat and polymer-modified asphalt cement. These Chip Seals were fabricated with various aggregate combinations to emphasize aggregate retention in cold climates with the accelerated Chip Seal simulation device. Three aggregate types at low temperatures were used to compare the aggregate retention performances of neat versus modified asphalt cement. A major finding of this research was that polymer modification of neat asphalt cement improved aggregate retention performance. In addition, results showed that a decrease in temperature causes increasing aggregate loss.
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Effect of aggregate surface properties on Chip Seal retention performance
Construction and Building Materials, 2013Co-Authors: Bekir Aktaş, Mustafa Karaşahin, Mehmet Saltan, Cahit GürerAbstract:Abstract A common distress type of Chip Seals is scabbing (loss of aggregate) which is caused by insufficient adhesion between aggregate and binder. Both the physical and chemical properties of the aggregate and binder play important roles on aggregate binder adhesion. This study focuses on evaluating the effects of aggregate surface properties on adhesion performance of Chip Seals using Accelerated Chip Seal Simulation Device (HSKSC) test procedure. 100/150 penetration neat and modified bitumen were used in experiments as binder. Also, clean, dusty and precoated forms of three different type aggregates were used in HSKSC tests. The results showed that performance of precoated aggregate considerably better in compare to dusty and clean aggregate. In addition modified binder demonstrated better Chip retention than the neat binder.
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Effects of construction-related factors on Chip Seal performance
Construction and Building Materials, 2012Co-Authors: Cahit Gürer, Mustafa Karaşahin, Sedat Çetin, Bekir AktaşAbstract:Abstract Chip Seal is an economical type of asphalt pavement that is widely used in countries such as Turkey, Australia, South Africa and New Zealand. However, unlike hot mix asphalt pavements, the performance of this type of pavement can be affected by many different parameters. Although these parameters have been identified in the literature, the extent to which each of these parameters affects the performance of Chip Seal has not yet been determined. The leading parameters affecting Chip Seal performance are those related to construction, including the adhesion capability of the aggregate used in construction, natural dust amount of the aggregate, ambient temperature during construction, bitumen temperature in the bitumen distributor tanks, time between bitumen spraying and aggregate spreading, time between aggregate spreading and rolling, time between construction stages, surface temperature during construction, aggregate and bitumen designs, in situ plate test values and per cent embedment of the aggregates. To determine the effect of these construction parameters on pavement performance, they were observed and measured on five test roads. The Chip-Sealed test roads were monitored for 1 year with nondestructive tests and observations to determine which construction-related parameters affect the performance of the pavement. The study results indicated that macrotexture loss is the most important deterioration factor in Chip-Sealed pavements; initial texture depth is also important with respect to the long-term performance of Chip-Sealed pavements. Rolling operations is another important factor for the performance of Chip Seal. If rolling operations are performed at high ambient temperatures, the per cent embedment of the aggregate will increase, causing the Chip Seal to deteriorate more rapidly. Consequently, the ambient temperature during the construction of Chip Seal is important; thus, Chip Seal should not be constructed at ambient temperatures lower than 30 °C or higher than 43.5 °C.
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Determination of the Performance of Chip Seal, Applied With HSKSC (Accelerated Chip Seal Simulation Device) on Unbound Base
2011Co-Authors: Mustafa Karaşahin, Cahit Gürer, Murat Vergi Taciroglu, Bekir AktaşAbstract:Chip Seals applied on unbound granular base are an asphalt pavement type that is widely used in countries such as Turkey, Australia, New Zealand, and South Africa. Although several methods and techniques regarding design of Chip Seals and measurement of performance of Chip Seal on-site and under laboratory conditions have been developed in recent years, there is no evidence that a device, system or method, allowing cost-effectively pre-measurement of performance of Chip Seals, existed in laboratory setting. In this study, Accelerated Chip Seal Simulation Device (HSKSC), which was developed and designed in Suleyman Demirel University (Turkey) and allows measurement of Chip Seal, applied on unbound granular base, under laboratory conditions and desired climate conditions as described, and results of two different performance tests performed with this device were discussed. Two different Chip Seals (single-layer and double-layer) were designed with this device and double-layer, single-layer Chip Seal samples were subjected to performance test in the device under a mild climate and hot climate respectively. During the tests, macro surface texture and numbers of friction-skid resistance were measured. As the number of cycles increases considerable decrease appeared particularly on macro texture and a limited decrease in micro texture. It was concluded that the performance tests to be carried out by means of prototype Accelerated Chip Seal Simulation Device (HSKSC) would be useful for design of Chip Seal applied on unbound granular bases.
Mohamed A. Elgawady - One of the best experts on this subject based on the ideXlab platform.
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retention behavior of crumb rubber as an aggregate in innovative Chip Seal surfacing
Journal of Cleaner Production, 2018Co-Authors: Ahmed Gheni, Steven Michael Lusher, Mohamed A. ElgawadyAbstract:Abstract Statistics show that the world's transportation infrastructures are a primary contributor to global greenhouse gas emissions. This paper introduces an innovative Chip Seal pavement surfacing that uses crumb rubber made from recycled tires as aggregates. A broad investigation on aggregate retention was performed. Eighty Chip Seal specimens with varied aggregate and binder parameters were examined for aggregate retention under five tests namely, the standard sweep test, a modified sweep test, the Vialit test, a modified Vialit test, and the Pennsylvania test. Four asphalt-based binders were examined including different types of emulsions and asphalt cement. Two mineral aggregates were examined in the tested specimens in addition to the crumb rubber. Results showed that the crumb rubber performed well in terms of aggregate retention. The Vialit and Pennsylvania tests indicated that the crumb rubber Chip Seal exceeded the performance of the mineral aggregate Chip Seals in terms of aggregate retention. The enhanced performance was primarily due to the low unit weight of the crumb rubber and its rough surface, that strengthened the adhesion of the crumb rubber to the binder. The sweep test results show that the mineral aggregate in Chip Seal surfacing can be replaced up to 100% with crumb rubber but it is recommended to increase the curing time before opening the roads for traffic due to the negligible water absorption capacity of crumb rubber.
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crumb rubber as a sustainable aggregate in Chip Seal pavement
Congrès International de Géotechnique – Ouvrages – Structures, 2017Co-Authors: Ahmed Gheni, Mohamed A. ElgawadyAbstract:The U.S. companies need to mine billions of tons of raw natural aggregates each year. In the same time, billions of scrap tires are going to landfills every year which makes the replacement of using natural aggregate with recycled and sustainable one is more beneficial to both industry and environment. This paper presents an extensive study on the performance of the Chip Seal pavement surfaces in terms of aggregate retention and performance. This study introduces a new eco-friendly Chip Seal by implementing the crumb rubber made of recycled tires as aggregates for such surface dressing. Twenty four specimens of Chip Seal were prepared and tested under three tests investigating the aggregate retention. The tests included the standard Vialit test, modified Vialit test, and sand patch test. Two types of emulsions, two types of binders, and three types of aggregates including the crumb rubber were examined in the tested specimens. This study revealed that the crumb rubbers from recycled tires would be used in the Chip Seal as aggregates but it is preferable to be used in conjunction with the conventional aggregates. The crumb rubber showed a remarkable performance in aggregate retention. This performance was mainly because of the low weight of the crumb rubber and its rough surface, which increased holding the crumb rubber into the asphalt emulsion or binder. In addition, crumb rubber as a partial or total replacement for the mineral aggregate was successfully implemented in the field using the traditional procedure and equipment.
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Texture and design of green Chip Seal using recycled crumb rubber aggregate
Journal of Cleaner Production, 2017Co-Authors: Ahmed Gheni, Omar I. Abdelkarim, Mohanad M. Abdulazeez, Mohamed A. ElgawadyAbstract:The depletion of natural resources forces the construction industry to explore using cleaner recycled material as replacements of virgin construction materials. A new eco-friendly Chip Seal pavement, in which the mineral aggregate was replaced by crumb rubber obtained from scrap tires, was investigated in this study. A total of 142 Chip Seal specimens were prepared and tested to investigate the impact of using recycled rubber aggregate on the Chip Seal's micro and macro texture and their impacts on the skid resistance. The microtexture of the new proposed recycled aggregate was examined using a high-resolution 3D digital microscope. The macrotexture of the new Chip Seal pavement was examined using image processing and sand patch methods. The skid resistance of the new Chip Seal under both ambient and elevated temperatures was then explored. Two types of emulsions, two types of asphalt cement binders, two types of mineral aggregate as well as two types of recycled crumb rubber were involved in the examined test matrix. This study concluded that the crumb rubber can be used in the Chip Seal as partial or full replacement of mineral aggregates. Using crumb rubber has a significant impact on improving both macrotexture and microtexture of Chip Seal. In addition, the low thermal conductivity of crumb rubber helped the Chip Seal resist elevated temperature without significant loss in skid resistance. A 3D geometrical model was then proposed to simulate the aggregate embedment so it can be used to design the required binder application rate that provides adequate embedment depth and skid resistance.
Ahmed Gheni - One of the best experts on this subject based on the ideXlab platform.
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retention behavior of crumb rubber as an aggregate in innovative Chip Seal surfacing
Journal of Cleaner Production, 2018Co-Authors: Ahmed Gheni, Steven Michael Lusher, Mohamed A. ElgawadyAbstract:Abstract Statistics show that the world's transportation infrastructures are a primary contributor to global greenhouse gas emissions. This paper introduces an innovative Chip Seal pavement surfacing that uses crumb rubber made from recycled tires as aggregates. A broad investigation on aggregate retention was performed. Eighty Chip Seal specimens with varied aggregate and binder parameters were examined for aggregate retention under five tests namely, the standard sweep test, a modified sweep test, the Vialit test, a modified Vialit test, and the Pennsylvania test. Four asphalt-based binders were examined including different types of emulsions and asphalt cement. Two mineral aggregates were examined in the tested specimens in addition to the crumb rubber. Results showed that the crumb rubber performed well in terms of aggregate retention. The Vialit and Pennsylvania tests indicated that the crumb rubber Chip Seal exceeded the performance of the mineral aggregate Chip Seals in terms of aggregate retention. The enhanced performance was primarily due to the low unit weight of the crumb rubber and its rough surface, that strengthened the adhesion of the crumb rubber to the binder. The sweep test results show that the mineral aggregate in Chip Seal surfacing can be replaced up to 100% with crumb rubber but it is recommended to increase the curing time before opening the roads for traffic due to the negligible water absorption capacity of crumb rubber.
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crumb rubber as a sustainable aggregate in Chip Seal pavement
Congrès International de Géotechnique – Ouvrages – Structures, 2017Co-Authors: Ahmed Gheni, Mohamed A. ElgawadyAbstract:The U.S. companies need to mine billions of tons of raw natural aggregates each year. In the same time, billions of scrap tires are going to landfills every year which makes the replacement of using natural aggregate with recycled and sustainable one is more beneficial to both industry and environment. This paper presents an extensive study on the performance of the Chip Seal pavement surfaces in terms of aggregate retention and performance. This study introduces a new eco-friendly Chip Seal by implementing the crumb rubber made of recycled tires as aggregates for such surface dressing. Twenty four specimens of Chip Seal were prepared and tested under three tests investigating the aggregate retention. The tests included the standard Vialit test, modified Vialit test, and sand patch test. Two types of emulsions, two types of binders, and three types of aggregates including the crumb rubber were examined in the tested specimens. This study revealed that the crumb rubbers from recycled tires would be used in the Chip Seal as aggregates but it is preferable to be used in conjunction with the conventional aggregates. The crumb rubber showed a remarkable performance in aggregate retention. This performance was mainly because of the low weight of the crumb rubber and its rough surface, which increased holding the crumb rubber into the asphalt emulsion or binder. In addition, crumb rubber as a partial or total replacement for the mineral aggregate was successfully implemented in the field using the traditional procedure and equipment.
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Texture and design of green Chip Seal using recycled crumb rubber aggregate
Journal of Cleaner Production, 2017Co-Authors: Ahmed Gheni, Omar I. Abdelkarim, Mohanad M. Abdulazeez, Mohamed A. ElgawadyAbstract:The depletion of natural resources forces the construction industry to explore using cleaner recycled material as replacements of virgin construction materials. A new eco-friendly Chip Seal pavement, in which the mineral aggregate was replaced by crumb rubber obtained from scrap tires, was investigated in this study. A total of 142 Chip Seal specimens were prepared and tested to investigate the impact of using recycled rubber aggregate on the Chip Seal's micro and macro texture and their impacts on the skid resistance. The microtexture of the new proposed recycled aggregate was examined using a high-resolution 3D digital microscope. The macrotexture of the new Chip Seal pavement was examined using image processing and sand patch methods. The skid resistance of the new Chip Seal under both ambient and elevated temperatures was then explored. Two types of emulsions, two types of asphalt cement binders, two types of mineral aggregate as well as two types of recycled crumb rubber were involved in the examined test matrix. This study concluded that the crumb rubber can be used in the Chip Seal as partial or full replacement of mineral aggregates. Using crumb rubber has a significant impact on improving both macrotexture and microtexture of Chip Seal. In addition, the low thermal conductivity of crumb rubber helped the Chip Seal resist elevated temperature without significant loss in skid resistance. A 3D geometrical model was then proposed to simulate the aggregate embedment so it can be used to design the required binder application rate that provides adequate embedment depth and skid resistance.
Scott Shuler - One of the best experts on this subject based on the ideXlab platform.
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Successful High Traffic Chip Seal Construction
1992Co-Authors: Scott ShulerAbstract:Chip Seal coats are used to extend pavement service life by reducing water and air infiltration and improving skid resistance. Application of Chip Seals is usually limited to low-traffic volume facilities for several reasons. This paper describes the first of four experimental field projects designed to demonstrate the potential use and effectiveness of Chip Seal applications on high traffic volume asphalt concrete pavements. This report documents the successful construction of three of these full scale experiments and the several types of Chip Seal treatments placed. Methods used for calibration of equipment, traffic control. design, and construction process essential for successful application of Chip Seals on high traffic pavements are described. In addition, a promising new version of a laboratory test is described as a method of predicting adhesive qualities of Chip Seal binders in advance of construction.
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HIGH-TRAFFIC Chip-Seal CONSTRUCTION: THE TULSA TEST ROAD
Transportation Research Record, 1991Co-Authors: Scott ShulerAbstract:Chip-Seal coats are used to extend pavement service life by reducing water and air infiltration and improving skid resistance. Application of Chip Seals is usually limited to low-traffic volume facilities because of unknown cost-effectiveness, vehicle damage caused by stones, inattention to proper principles, traffic disruption, and inappropriate design procedures. The causes of the problems that discourage use of Chip-Seal coats on high-traffic-volume pavements were investigated in this research project such that wider use of this potentially cost-effective construction process can be developed. The first of four experimental field projects designed to demonstrate the potential use and effectiveness of Chip-Seal applications on high-traffic-volume asphalt concrete pavements is described. The successful construction of the first of these full-scale experiments and the several types of Chip-Seal treatments placed are documented. Methods used for calibration of equipment, traffic control, design, and construction processes essential for successful application of Chip Seals on high-traffic pavements are described. In addition, a promising new version of a laboratory test is described as a method of predicting adhesive qualities of Chip-Seal binders in advance of construction.