Evaluation of Long-Term Oven Aging of Asphalt Mixtures (AASHTO PP2-95) on Superpave Thermal Cracking Performance Predictions

Evaluation of Long-Term Oven Aging of Asphalt Mixtures (AASHTO PP2-95) on Superpave Thermal Cracking Performance Predictions PDF Author: P. Romero
Publisher:
ISBN:
Category : Aging
Languages : en
Pages : 18

Get Book Here

Book Description
A study was conducted to determine the effects of long term oven aging of asphalt mixtures (AASHTO PP2-95) on the thermal cracking performance evaluation of mixtures using the SUPERPAVE Indirect Tensile Test (IDT). Asphalt mixtures were aged according to the procedures developed by the Strategic Highway Research Program (SHRP) and tested using the SUPERPAVE Indirect Tensile Test after short- and long-term oven aging. The results were used to make thermal cracking performance predictions using the Penn State Thermal Cracking Model, which is a part of the SUPERPAVE mixture analysis system. The analyses indicated that: 1) long-term oven aging of mixtures produced changes in mixture compliance that led to differences in thermal cracking performance predictions, 2) long-term oven aging can produce excessive aging which results in erroneous (unconservative) performance predictions and 3) the relative ranking of thermal cracking performance of short-term oven-aged mixtures is, for most cases, the same as that of long-term oven aged mixtures. In other words, the system distinguished between mixtures with significantly different performance levels regardless of whether the mixtures were tested after short-term oven aging or long-term oven aging. This finding implies that long-term oven aging may not be justified for mixture specification purposes when the SUPERPAVE low temperature performance evaluations are used.

Evaluation of Long-Term Oven Aging of Asphalt Mixtures (AASHTO PP2-95) on Superpave Thermal Cracking Performance Predictions

Evaluation of Long-Term Oven Aging of Asphalt Mixtures (AASHTO PP2-95) on Superpave Thermal Cracking Performance Predictions PDF Author: P. Romero
Publisher:
ISBN:
Category : Aging
Languages : en
Pages : 18

Get Book Here

Book Description
A study was conducted to determine the effects of long term oven aging of asphalt mixtures (AASHTO PP2-95) on the thermal cracking performance evaluation of mixtures using the SUPERPAVE Indirect Tensile Test (IDT). Asphalt mixtures were aged according to the procedures developed by the Strategic Highway Research Program (SHRP) and tested using the SUPERPAVE Indirect Tensile Test after short- and long-term oven aging. The results were used to make thermal cracking performance predictions using the Penn State Thermal Cracking Model, which is a part of the SUPERPAVE mixture analysis system. The analyses indicated that: 1) long-term oven aging of mixtures produced changes in mixture compliance that led to differences in thermal cracking performance predictions, 2) long-term oven aging can produce excessive aging which results in erroneous (unconservative) performance predictions and 3) the relative ranking of thermal cracking performance of short-term oven-aged mixtures is, for most cases, the same as that of long-term oven aged mixtures. In other words, the system distinguished between mixtures with significantly different performance levels regardless of whether the mixtures were tested after short-term oven aging or long-term oven aging. This finding implies that long-term oven aging may not be justified for mixture specification purposes when the SUPERPAVE low temperature performance evaluations are used.

Progress of Superpave (superior Performing Asphalt Pavement)

Progress of Superpave (superior Performing Asphalt Pavement) PDF Author: Robert N. Jester
Publisher: ASTM International
ISBN: 080312418X
Category : Asphalt
Languages : en
Pages : 223

Get Book Here

Book Description
A major result of the research conducted under the Strategic Highway Research Program from 1987 to 1993 was the development of the Superpave (Superior Performing Asphalt Pavement) system for the comprehensive design of asphalt pavements. These 14 contributions describe the experience to date in the

Dissertation Abstracts International

Dissertation Abstracts International PDF Author:
Publisher:
ISBN:
Category : Dissertations, Academic
Languages : en
Pages : 756

Get Book Here

Book Description


Long-term Aging of Asphalt Mixtures for Performance Testing and Prediction

Long-term Aging of Asphalt Mixtures for Performance Testing and Prediction PDF Author: Y. Richard Kim
Publisher:
ISBN: 9780309446839
Category : Pavements, Asphalt
Languages : en
Pages : 104

Get Book Here

Book Description


Long-term Aging of Asphalt Mixtures for Performance Testing and Prediction

Long-term Aging of Asphalt Mixtures for Performance Testing and Prediction PDF Author: Y. Richard Kim
Publisher:
ISBN: 9780309674164
Category : Accelerated life testing
Languages : en
Pages : 182

Get Book Here

Book Description
TRB's National Cooperative Highway Research Program (NCHRP) Research Report 973: Long-Term Aging of Asphalt Mixtures for Performance Testing and Prediction: Phase III Results refines the aging procedure developed in the original NCHRP Research Report 871: Long-Term Aging of Asphalt Mixtures for Performance Testing and Prediction. The updates field calibrate the original project aging model (PAM), develop procedures to estimate the PAM inputs, and develop a framework by which the predicted changes in asphalt binder properties that are due to oxidative aging can be related to corresponding changes in asphalt mixture performance.

Summary Report on Aging of Asphalt-aggregate Systems

Summary Report on Aging of Asphalt-aggregate Systems PDF Author: Chris A. Bell
Publisher:
ISBN:
Category : Aggregates (Building materials)
Languages : en
Pages : 128

Get Book Here

Book Description
This is a report on the state of the art of research on the phenomenon of the aging of asphalt-aggregate mixtures. Compared to research on the aging of asphalt cement, there has been little research on the aging of asphalt mixtures. Binder studies are considered as well as mixture sutdies, the relationship between laboratory aging tests and field performance, and the relationship between chemical composition and field performance. Recommendations are made for aging procedures which show promise for laboratory investigation. Test methods to evaluate aging are also considered. It is noted that extended heating procedures show the most promise for short-term aging and pressure oxidation and/or extended heating the most promise for long-term aging.

Aging Characterization of Foamed Warm Mix Asphalt

Aging Characterization of Foamed Warm Mix Asphalt PDF Author: Mir Shahnewaz Arefin
Publisher:
ISBN:
Category : Asphalt
Languages : en
Pages : 129

Get Book Here

Book Description
This study evaluated the aging characteristic of foamed warm mix asphalt (WMA) produced by water injection in comparison to traditional hot mix asphalt (HMA). Four types of asphalt binders (PG 64-22, PG 64-28, PG 70-22, PG 76-22) were used in the preparation of the foamed WMA and HMA mixtures. All mixtures were prepared using limestone aggregates with a nominal maximum aggregate size (NMAS) of 12.5 mm that met the Ohio Department of Transportation (ODOT) Construction and Material Specifications (C&MS) for Item 442 (Superpave Asphalt Concrete).The short-term and long-term aging of the asphalt binders were simulated using the rolling thin film oven (RTFO) and the pressure aging vessel (PAV), respectively, while the short-term and long-term aging of the laboratory-prepared asphalt mixtures were simulated according to AASHTO R 30 (Mixture Conditioning of Hot Mix Asphalt).The dynamic shear rheometer (DSR) was used to characterize the viscoelastic behavior of the unaged, RTFO-aged, and PAV-aged asphalt binders, while the dynamic modulus (lE*l) test was used to characterize the viscoelastic behavior of the short-term and long-term aged foamed WMA and HMA mixtures.In addition, the mechanistic-empirical pavement design guide (MEPDG) global aging model was used to predict the effect of aging on the dynamic modulus (lE*l) of foamed WMA and HMA mixtures, and the MEPDG global aging model predictions were compared to dynamic modulus (lE*l) test results obtained in the laboratory for both asphalt mixtures. By comparing the DSR test results following RTFO and PAV to those obtained for the unaged asphalt binders, it was observed that PG 64-22 was the least susceptible to aging followed by PG 70-22, PG 76-22, and PG 64-28. Similar trends were also observed from the dynamic modulus test, where little difference was noticed between the short-term and long-term aged specimens prepared using PG 64-22 for both foamed WMA and HMA mixtures.The dynamic modulus test results also revealed slightly lower lE*l values for foamed WMA mixtures in comparison to traditional HMA mixtures. This indicates that foamed WMA mixtures are slightly more susceptible to rutting than HMA mixtures. However, by comparing the dynamic modulus of the long-term aged specimens to the short-term aged specimens, it was observed that the increase in stiffness for the foamed WMA mixtures was less than that for the traditional HMA mixtures. This indicates that foamed WMA mixtures are less susceptible to aging and subsequently fatigue cracking than HMA mixtures.Finally, by the comparing the MEPDG global aging model predictions to the dynamic modulus test results for both foamed WMA and HMA mixtures, it was observed that the MEPDG global aging model provided more reasonable predictions, especially at higher frequencies, but overestimated or underestimated the dynamic modulus at lower frequencies. This was observed for both foamed WMA and HMA mixtures, which suggests that this model can be used for both types of mixtures.

Development of the SHRP Superpave Mixture Specification Test Method to Control Thermal Cracking Performance of Pavements

Development of the SHRP Superpave Mixture Specification Test Method to Control Thermal Cracking Performance of Pavements PDF Author: WG. Buttlar
Publisher:
ISBN:
Category : Asphalt emulsion mixtures
Languages : en
Pages : 19

Get Book Here

Book Description
The indirect tensile creep and failure test at low temperatures (ITLT) was selected by SHRP to control thermal cracking performance within the SUPERPAVE mixture design and analysis system. Fundamental viscoelastic properties and fracture parameters obtained from the test are used in the SUPERPAVE thermal cracking model to predict thermal cracking performance (cracking as a function of time) of asphalt pavements of variable thicknesses in different temperature regimes. This approach gives pavement and mixture designers the capability of determining not only that one mixture is better than another, but also quantifies how much better one mixture is than another in terms of its cracking performance. The background and principles used to identify this test method are presented in this paper along with the results of analytical and laboratory work conducted to identify specific test procedures. Comparisons between cracking predicted using ITLT test results and observed cracking in over 35 test sections in the United States and Canada have indicated that this test is suitable for control of thermal cracking of asphalt mixtures.

Prediction of Low Temperature Cracking of Asphalt Concrete Mixtures with Thermal Stress Restrained Specimen Test Results

Prediction of Low Temperature Cracking of Asphalt Concrete Mixtures with Thermal Stress Restrained Specimen Test Results PDF Author: Hannele K. Kanerva
Publisher:
ISBN:
Category : Pavements, Asphalt concrete
Languages : en
Pages : 358

Get Book Here

Book Description
Low temperature cracking is attributed to tensile stresses induced in an asphalt concrete pavement that develop when the pavement is subjected to a cold temperature. Cracking results in poor ride quality and a reduction in service life of the pavement. Low temperature cracking has been predicted by regression equations, mechanistic approaches and by simulation measurements. The purpose of the study reported herein is to (1) evaluate the Thermal Stress Restrained Specimen Test (TSRST) as an accelerated performance test to simulate low temperature cracking of asphalt concrete mixtures and (2) develop a deterministic and probabilistic model to predict low temperature cracking with TSRST results. Construction histories, cracking observations and temperature data were collected for five test roads in Alaska, Pennsylvania and Finland. A full scale and fully controlled low temperature cracking test program was conducted at the U.S. Army Cold Regions Research and Engineering Laboratory (USACRREL). Specimens were fabricated in the laboratory with original asphalt cements and aggregates from the test roads. In addition, asphalt concrete pavement specimens were cut from the test sections. The TSRST results obtained for these samples were correlated with the field observations. Based on a statistical analysis of the data, the TSRST fracture temperature is associated with the field cracking temperature and crack frequency for the test roads where mixture properties dominated low temperature cracking. It was concluded that the TSRST can be used to simulate low temperature cracking of asphalt concrete mixtures. A deterministic and a probabilistic model were developed to predict crack spacing as a function of time using the TSRST results, pavement thickness and bulk density, pavement restraint conditions and air temperature. The affect of aging on pavement properties was incorporated in the models by predicting the field aging with Long Term Oven Aging (LTOA) treatment in the laboratory. The calculation of the crack spacing is based on the theory that the pavement slab cracks when the pavement temperature reaches the cracking temperature of the mixture and the slab is fully restrained. The deterministic model predicts crack spacing with time whereas the probabilistic model predicts crack spacing and its variation with time and yields the reliability of the design with regard to a minimum acceptable crack spacing criterion defined by road authorities. The models were verified by comparing the predicted crack spacings for the five test roads to the observed crack spacings. The probabilistic model is recommended for use in predicting the low temperature cracking of asphalt concrete mixtures.

Evaluation of Indirect Tensile Test (IDT) Procedures for Low-temperature Performance of Hot Mix Asphalt

Evaluation of Indirect Tensile Test (IDT) Procedures for Low-temperature Performance of Hot Mix Asphalt PDF Author: Donald W. Christensen
Publisher: Transportation Research Board National Research
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 68

Get Book Here

Book Description