Assessment of Asphalt Interlayer Designed on Jointed Concrete PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Assessment of Asphalt Interlayer Designed on Jointed Concrete PDF full book. Access full book title Assessment of Asphalt Interlayer Designed on Jointed Concrete by R. Christopher Williams. Download full books in PDF and EPUB format.
Author: R. Christopher Williams Publisher: ISBN: Category : Pavements, Asphalt concrete Languages : en Pages : 37
Book Description
Reflective cracking in hot mix asphalt (HMA) overlays has been a common cause of poor pavement performance in Iowa for many years. Reflective cracks commonly occur in HMA overlays when deteriorated portland cement concrete is paved over with HMA. This results in HMA pavement surfaces with poor ride quality and increased transportation maintenance costs. To delay the formation of cracks in HMA overlays, the Iowa Department of Transportation (Iowa DOT) has begun to implement a crack-relief interlayer mix design specification. The crack-relief interlayer is an asphalt-rich, highly flexible HMA that can resist cracking in high strain loading conditions. In this project, the field performance of an HMA overlay using a one inch interlayer was compared to a conventional HMA overlay without an interlayer. Both test sections were constructed on US 169 in Adel, Iowa as part of an Iowa DOT overlay project. The laboratory performance of the interlayer mix design was assessed for resistance to cracking from repeated strains by using the four-point bending beam apparatus. An HMA using a highly polymer modified binder was designed and shown to meet the laboratory performance test criteria. The field performance of the overlay with the interlayer exceeded the performance of the conventional overlay that did not have the interlayer. After one winter season, 29 percent less reflective cracking was measured in the pavement section with the interlayer than the pavement section without the interlayer. The level of cracking severity was also reduced by using the interlayer in the overlay.
Author: R. Christopher Williams Publisher: ISBN: Category : Pavements, Asphalt concrete Languages : en Pages : 37
Book Description
Reflective cracking in hot mix asphalt (HMA) overlays has been a common cause of poor pavement performance in Iowa for many years. Reflective cracks commonly occur in HMA overlays when deteriorated portland cement concrete is paved over with HMA. This results in HMA pavement surfaces with poor ride quality and increased transportation maintenance costs. To delay the formation of cracks in HMA overlays, the Iowa Department of Transportation (Iowa DOT) has begun to implement a crack-relief interlayer mix design specification. The crack-relief interlayer is an asphalt-rich, highly flexible HMA that can resist cracking in high strain loading conditions. In this project, the field performance of an HMA overlay using a one inch interlayer was compared to a conventional HMA overlay without an interlayer. Both test sections were constructed on US 169 in Adel, Iowa as part of an Iowa DOT overlay project. The laboratory performance of the interlayer mix design was assessed for resistance to cracking from repeated strains by using the four-point bending beam apparatus. An HMA using a highly polymer modified binder was designed and shown to meet the laboratory performance test criteria. The field performance of the overlay with the interlayer exceeded the performance of the conventional overlay that did not have the interlayer. After one winter season, 29 percent less reflective cracking was measured in the pavement section with the interlayer than the pavement section without the interlayer. The level of cracking severity was also reduced by using the interlayer in the overlay.
Author: Harikrishnan Nair Publisher: ISBN: Category : Pavements Languages : en Pages : 37
Book Description
Propagation of cracks from existing pavements into a new asphalt concrete overlay (reflective cracking) is a major problem for both rigid and flexible pavements. Reflective cracking in pavements compromises ride quality and reduces the service life of the pavement. Reflective cracking of the asphalt layer over jointed concrete pavement is a perennial problem in Virginia and elsewhere. State transportation agencies continue to try various available treatment methods to delay or prevent reflective cracking with corrective or restorative maintenance. Some of those treatments include using paving fabric as an interlayer. Virginia has anecdotal experience with paving fabric interlayers, but little well-documented history with which to assess performance. The objective of this study was to establish a performance baseline for fabric interlayers in conjunction with asphalt concrete overlays on existing flexible, rigid, and composite pavements by documenting the installation and initial field performance of several projects in Virginia. Two types of interlayer fabric were used. One of the interlayers needed an asphalt leveling course for placement based on the manufacturer's specifications. As expected, all of the sections with interlayers are performing well. However, most of the sections were placed in 2017 and 2018, and hence the performance data are preliminary. These sections need to be monitored continuously to track pavement distress and performance over time. The cost of using interlayers in pavement ranged from 6 .0 dollars to 8 .0 dollars per square yard, depending on the type of fabric and installation method. Long-term performance data are needed to assess the benefit-cost effectiveness of using paving fabric interlayers in pavements.
Author: L. Francken Publisher: CRC Press ISBN: 1482271796 Category : Architecture Languages : en Pages : 576
Book Description
Proceedings of RILEM TC-PRC third conference on this subject. Papers from road authorities, engineers, researchers, contractors and manufacturers discussing the implementation and the long term behaviour of overlay systems. The following topics are covered: prevention and cracking assessment, choice and design of overlay systems, practical implemen
Author: M. T. Mukhtar Publisher: ISBN: Category : Geosynthetics Languages : en Pages : 268
Book Description
To approach the reflection cracking problem in asphalt concrete (AC) overlays systematically the properties of the materials intended to be used in an interlayer stress absorbing composite (ISAC) system were first identified. Various thermal/structural models and laboratory equipment were used for this purpose. A number of woven and nonwoven geotextiles were selected and tested for their engineering properties such as tensile strength, initial modulus, modulus at failure, and percent shrinkage. Several samples of rubber asphalt were prepared by blending different ratios of crumb rubber with various types and ratios of asphalt cements at 400 deg F. These rubber asphalts were tested at different temperatures and the effects of temperature and rate of deformation on their stiffness were evaluated. An ISAC layer was fabricated in the laboratory using the materials considered appropriate. Testing equipment was developed to evaluate the interfacial shear strength and laboratory testing was performed to determine the shear strength of the fabricated ISAC layer under an AC overlay. The ISAC layer was evaluated for its effectiveness against reflection cracking. A laboratory pavement section with an AC overlay over a jointed portland cement concrete slab was constructed and placed in an environmental chamber. A mechanical device was used to simulate thermal strain in the slab and the joint was opened and closed at an extremely slow rate. The testing was conducted at 30 deg F and deterioration in the overlay was monitored using a sensitive LVDT device. The results from the laboratory evaluation testing program indicated that the ISAC layer was highly effective in preventing reflection cracking in a 2.5-in. AC overlay. When compared to a control test section and a section using a commercially available reflection cracking control material, the ISAC layer provided for superior performance. A field pavement test section utilizing the ISAC layer was constructed in the Summer of 1994 and field evaluation is ongoing.
Author: Harikrishnan Nair Publisher: ISBN: Category : Asphalt concrete-Additives Languages : en Pages : 0
Book Description
Ground tire rubber (GTR) from scrap tires is used in asphalt mixtures (rubber modified asphalt [RMA]) for improving the performance of pavements. There are different ways to add GTR in asphalt mixtures, but the two primary methods are referred to as the “wet” and “dry” processes. The dry process incorporates GTR directly into the asphalt mixture during production (directly to the aggregates through the reclaimed asphalt pavement collar). The Virginia Department of Transportation (VDOT) has limited experience with RMA mixtures in Superpave dense-graded mixtures using the dry process, but the relative ease of mixture production makes the dry process an attractive option for RMA. In the fall of 2019, VDOT placed a dense-graded RMA mixture, SM 12.5 (GTR), on US 60 in VDOT’s Richmond District (New Kent County). This was the first use of a SM 12.5 (GTR) mixture in Virginia using the dry process method. The purpose of this study was to establish a performance baseline for a GTR modified dense-graded asphalt mixture that was designed and produced using the dry process. The US 60 project also included the use of a thin hot mix asphalt concrete overlay (THMACO) as an interlayer. An assessment of the THMACO as an interlayer was a secondary objective of the study. The study found that dry process SM 12.5 (GTR) mixture can be produced and placed with no significant field-related concerns and that the special provision developed for its use was effective. Density requirements were achieved, and the as-placed mat had excellent (very low) permeability characteristics. Laboratory performance testing showed the SM 12.5 (GTR) mixture to be more crack resistant than conventionally modified polymer (SM 12.5E) mixtures. Conventionally modified SM E mixtures had slightly better rutting performance. However, this conclusion was based on performance testing and thresholds that were developed for non-modified asphalt mixtures. Additional laboratory and field performance comparison is needed to develop mixture acceptance criteria for GTR mixtures. Further, THMACO mixtures had excellent laboratory reflective cracking resistance properties. They performed particularly well in the Texas overlay test. Grading of extracted (from the asphalt mixture) binder may not provide an accurate representation of the binder performance for the dry process GTR modified asphalt. Continued monitoring of performance will be needed to quantify any benefit of SM 12.5 (GFR) mixtures in comparison with regular SM E mixtures. The study recommends additional field trials with SM 12.5 (GTR) mixtures for performance evaluation. Further, the study recommends continued use of a THMACO as an interlayer to mitigate reflective cracking for composite pavements.
Author: J.M. Rigo Publisher: CRC Press ISBN: 1482271249 Category : Architecture Languages : en Pages : 512
Book Description
This book forms the Proceedings of the Second International RILEM Conference held in Liege in March 1993. It follows the successful first conference held in 1989 and focusses on two main topics: the current state of the art of reflective cracking in highway and other pavements, and design recommendations for field applications. As well as more than
Author: American Society of Civil Engineers Publisher: Amer Society of Civil Engineers ISBN: 9780784411049 Category : Technology & Engineering Languages : en Pages : 592
Book Description
Pavement Design And Paving Material Selection are important for efficient, cost effective, durable, and safe transportation infrastructure Paving Materials and Pavement Analysis contains 73 papers examining bound and unbound material characterization, modeling, and performance of highway and airfield pavements. The papers in this publication were presented during the GeoShanghal 2010 International Conference held in Shanghai, China, June 3-5, 2010.
Author: R. Christopher Williams
Author: R. Christopher Williams
Author: Harikrishnan Nair
Author: L. Francken
Author: M. T. Mukhtar
Author: 
Author: Harikrishnan Nair
Author: Debra L. Bischoff
Author: C. Petit
Author: J.M. Rigo
Author: American Society of Civil Engineers