Download or read book Development of Structural Layer Coefficients of Crumb Rubber modified Asphalt Mixes from In situ Deflection Tests written by Affan Habib and published by . This book was released on 1997 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report includes the results of testing Crumb Rubber Modified (CRM) asphalt to quantify the layer coefficient values for CRM mixes. Several test sections were selected from recently constructed CRM pavement. The Falling Weight Deflectometer (FWD) data were collected at 15 meter intervals on each test section during a one month period.
Download or read book Layer Coefficients for New and Reprocessed Asphaltic Mixes written by and published by . This book was released on 2000 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigation Into Deriving Layer Coefficients for New and Reprocessed Asphalt Mixtures written by John Donald Christensen and published by . This book was released on 1999 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of a Crumb Rubber Modified CRM Asphalt Concrete Mix Design written by Mustaque Hossain and published by . This book was released on 1995 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this project was to develop an asphalt mix design method incorporating crumb rubber and using the "Wet" or "Dry" method of producing Crumb Rubber Modified Asphalt (CRM). Several resurfacing projects have been constructed using both the "Wet" and "Dry" methods. Based on this study, the Kansas Department of Transportation could use CRM mixes with a binder content between 7.5% and 9.0% depending on the percent air voids, with 19% to 22% rubber content. In this study, it was observed that using 24% rubber produced mixes that were too sticky to manage. With a rubber content of less than 18% combined with AC-5 it was difficult to satisfy the minimum viscosity requirements. Fracture tests can be used as a basis to determine the optimum binder content for any asphalt-rubber mix.
Download or read book A Study of Flexural Fatigue Behavior of Asphalt rubber Mixes written by Mustaque Hossain and published by . This book was released on 1997 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this study is to evaluate the fatigue behavior of crumb-rubber modified asphalt. The research involved flexural fatigue testing of beams made with hot mix asphalt rubber using the wet process where the crumb rubber reacted with the asphalt at high temperature. Two types of asphalt rubber were studied: Asphalt Rubber Surface (ARS) and Asphalt Rubber Base (ARB). The ARS was a gap-graded aggregate mix with 0.5 in. (1.27 cm) maximum size and 7% design asphalt rubber content using CRM-III (minus #10 mesh) rubber. The ARB had a denser gradation with a 0.75 in. (3.81 cm) maximum aggregate size and 7% design asphalt rubber content also using CRM-III rubber.
Download or read book Transportation Research Record written by and published by . This book was released on 1997 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Estimation of Layer Coefficients for Flexible Pavement Design and Development of a Practical and Rational Mix design written by and published by . This book was released on 1994 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pavement layer coefficients had been identified as essential parameters to use the 1986/1993 AASHTO Guide for Design of Pavement Structures (AASHTO guide) in Rhode Island. Layer coefficients of granular subbase materials were estimated using the direct method recommended by AASHTO Guide. Resilient moduli were determined using a pneumatic testing system. Coefficients based on resilient moduli ranged from 0.08 to 0.14, and the average was 0.12 for eight subbase samples in Rhode Island. The pneumatic testing system was also used to determine resilient moduli of bound layeres. Based on results of a series of testing, layer coefficients were estimated using moduli at the loading magnitude of 20% of tensile strength and loading frequency of 0.5Hz. Recommended coefficients for wearing course (Class I-1), modified binder, and modified asphalt base were 0.40, 0.42, and 0.43, respectively. If all asphalt bound layers will be analyzed as one layer, the coefficient of 0.41 was recommended for pavement design and analysis in Rhode Island. Field study including FWD testing was performed to verify laboratory test results. Laboratory determined moduli were compared with backcalculated moduli based on FWD deflection data. Generally, FWD moduli are consistently higher than laboratory moduli with a wide range of variability. For the covering abstract of this conference, see IRRD number 863140.
Download or read book Thermal Behavior of Crumb rubber Modified Asphalt Concrete Mixtures written by Amy Epps Martin and published by . This book was released on 1997 with total page 826 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mixture Desigh sic and Performance Prediction of Rubber modified Asphalt in Ohio written by Robert Y. Liang and published by . This book was released on 1998 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: The mixture design and performance characteristics of crumb rubber modified asphalt concretes were investigated in this research project to meet the requirements of the Intermodal Surface Transportation Efficiency Act (ISTEA) of 1991, which has required each State to incorporate scrap tire rubber into its asphalt paving materials. Specifically, the objectives of this research encompass the following: (i) investigation of the rheological properties of asphalt-rubber binder to determine optimum content of crumb rubber; (ii) development of optimum mix design for various applications, including both wet and dry mix processes; (iii) characterization of mechanical properties of recommended paving mixtures, including resilient modulus, fatigue cracking behavior, low-temperature thermal cracking resistance, water sensitivity test, incremental creep test and loaded wheel track test; and (iv) comparison of performance of selected paving mixes.
Download or read book Development of a Crumb Rubber Modified CRM Asphalt Concrete Mix Design written by Md. Enamul Hoque and published by . This book was released on 1995 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of Procedure to Assign Structural Layer Coefficients for Use in Flexible Pavement Design written by Harold L. Von Quintus and published by . This book was released on 2007 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Kansas Department of Transportation (DOT) uses the 1993 DARWin version of the 1986 AASHTO Guide to design flexible pavements and rehabilitation strategies of flexible pavements. One of the inputs needed for the flexible pavement design procedure is the structural layer coefficient for each pavement layer. The Kansas DOT procedure to assign structural layer coefficients was developed years ago and based on an analysis of flexible pavement performance data and layer properties. It has been recently suggested that the Kansas DOT increase the structural layer coefficients because of changes in material and construction specifications. Different procedures can be used to estimate the structural layer coefficients for flexible pavement design. As part of the study entitled Determination of the Appropriate Use of Pavement Surface History in the KDOT Life-Cycle Cost Analysis Process an evaluation of the procedure that Kansas DOT uses to assign structural layer coefficients to different pavement materials was completed. This report provides the results of that evaluation.
Download or read book Structural Coefficients for New Asphalt Mixtures written by David H. Timm and published by . This book was released on 2005 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Layer Coefficients for Flexible Pavements written by Samuel H. Carpenter and published by . This book was released on 1990 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of Performance on Crumb Rubber Modified Asphalt Mixture written by Yuming Dong and published by . This book was released on 2012 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper investigates the performance of crumb-rubber-modified (CRM) asphalt mixture. Two different asphalt mixtures containing two types of asphalt binder (#90 original asphalt and CRM asphalt) were used to prepare Marshall specimens and determine optimum asphalt content. Mechanical performances of asphalt mixes were evaluated by the wheel rutting test (WRT) (dynamic stability (DS)), midpoint beam bend test (MBBT), at low temperature, and indirect tensile test (IDT), at the freezing and thawing cycle. Superpave gyratory compactor (SGC) specimens were also prepared for the modulus test. Using the simple performance test (SPT) and universal testing system (UTS), viscoelastic mechanical characteristics were evaluated by static and dynamic modulus tests. Static modulus (E) data were measured by the un-confinement uniaxial compression test according to the specification of China. Moreover, dynamic modulus (E0) data were obtained by SPT. The crumb-rubber content varies from 0, 10 %, 20 %, to 30 % at the static modulus test. Two test temperatures were selected for the dynamic modulus test. The results indicated that the CRM asphalt mixture performs better than the standard asphalt mixture on dynamic behavior, rutting resistance, cracking resistance, and moisture stability.
Download or read book AASHTO Guide for Design of Pavement Structures 1993 written by American Association of State Highway and Transportation Officials and published by AASHTO. This book was released on 1993 with total page 622 pages. Available in PDF, EPUB and Kindle. Book excerpt: Design related project level pavement management - Economic evaluation of alternative pavement design strategies - Reliability / - Pavement design procedures for new construction or reconstruction : Design requirements - Highway pavement structural design - Low-volume road design / - Pavement design procedures for rehabilitation of existing pavements : Rehabilitation concepts - Guides for field data collection - Rehabilitation methods other than overlay - Rehabilitation methods with overlays / - Mechanistic-empirical design procedures.
Download or read book Estimation of AASHTO Layer Coefficients for Bituminous Mixes written by Michael Eugene Ayers and published by . This book was released on 1993 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: The resilient modulus test procedure, as specified by the Strategic Highway Research Program (SHRP) P07 protocol, is used to evaluate Oklahoma Department of Transportation (ODOT) types A, B, and G asphalt concrete mixes. Structural layer coefficients are estimated based on the resilient modulus test results. A full face dynamic compaction apparatus was designed and constructed to allow fabrication of large aggregate asphalt concrete samples. The dynamic compaction apparatus is compared with the Marshall and gyratory compaction techniques. A comparison of 4-, 6-, and 8-in. (10.2-, 15.2-, and 20.4-cm) specimens is presented as is a thorough statistical analysis of the material and test variability.
Download or read book Performance Testing of Asphalt Concrete Containing Crumb Rubber Modifier and Warm Mix Additives written by and published by . This book was released on 2014 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: Utilisation of scrap tire has been achieved through the production of crumb rubber modified binders and rubberised asphalt concrete. Terminal and field blended asphalt rubbers have been developed through the wet process to incorporate crumb rubber into the asphalt binder. Warm mix asphalt technologies have been developed to curb the problem associated with the processing and production of such crumb rubber modified binders. Also the lowered production and compaction temperatures associated with warm mix additives suggests the possibility of moisture retention in the mix, which can lead to moisture damage. Conventional moisture sensitivity tests have not effectively discriminated good and poor mixes, due to the difficulty of simulating field moisture damage mechanisms. This study was carried out to investigate performance properties of crumb rubber modified asphalt concrete, using commercial warm mix asphalt technology. Commonly utilised asphalt mixtures in North America such as dense graded and stone mastic asphalt were used in this study. Uniaxial Cyclic Compression Testing (UCCT) was used to measure permanent deformation at high temperatures. Indirect Tensile Testing (IDT) was used to investigate low temperature performance. Moisture Induced Sensitivity Testing (MiST) was proposed to be an effective method for detecting the susceptibility of asphalt mixtures to moisture damage, as it incorporates major field stripping mechanisms. Sonnewarm(TM), Sasobit(TM) and Evotherm(TM) additives improved the resistance to permanent deformation of dense graded mixes at a loading rate of 0.5 percent by weight of the binder. Polymer modified mixtures showed superior resistance to permanent deformation compared to asphalt rubber in all mix types. Rediset(TM) WMX improves low temperature properties of dense graded mixes at 0.5 percent loading on the asphalt cement. Rediset LQ and Rediset WMX showed good anti stripping properties at 0.5 percent loading on the asphalt cement. The American Association of State Highway and Transportation Official's Mechanistic-Empirical Pavement Design Guide (AASHTO MEPDG) software was used to predict long term low temperature performance of the mixtures in various areas of Ontario. Sasobit, Rediset LQ and Rediset WMX gave good 15 years prediction with stone mastic asphalt mixtures but the performance of dense graded mixtures was less satisfactory.
