Influence of Selected Warm Mix Asphalt Additives on Cracking Susceptibility of Asphalt Mixtures

Warm mix asphalt (WMA) has been widely accepted as a future asphalt paving technology. Besides clear advantages, there are still some concerns regarding durability and long-term performance of pavements made with this type of asphalt mixtures. One of the most important issues is low temperature behaviour of WMA because certain additives used for temperature reduction can affect bitumen properties. This paper presents the evaluation of low-temperature properties of laboratory-produced asphalt concrete for wearing course with selected WMA additives. One type of bitumen with paving grade 50/70 and five WMA additives of different nature (organic, surface tension reducer and combination of both) were used in this study. The production and compaction temperature of mixtures containing WMA additives was 25 °C lower in comparison with the temperature of the reference mix. To assess the susceptibility of WMA to low-temperature cracking, Semi-Circular Bending (SCB) and Thermal Stress Restrained Specimen Test (TSRST) were used. Supplementary rating was made by analysing Bending Beam Rheometer (BBR) test results of asphalt binders.

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Long term performance of warm mix asphalt versus hot mix asphalt

Journal of Central South University ◽

10.1007/s11771-013-1483-1 ◽

2013 ◽

Vol 20 (1) ◽

pp. 256-266 ◽

Cited By ~ 17

Author(s):

Ziari Hasan ◽

Behbahani Hamid ◽

Izadi Amir ◽

Nasr Danial

Keyword(s):

Hot Mix Asphalt ◽

Warm Mix Asphalt ◽

Long Term Performance ◽

Term Performance

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Influence Analysis of Performance on Sasobit Warm Mix Asphalt with Salinity

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.490-491.138 ◽

2014 ◽

Vol 490-491 ◽

pp. 138-141

Author(s):

Kun Wang ◽

Jing Ya Chen ◽

Xiang Qu

Keyword(s):

Low Temperature ◽

Environmental Benefits ◽

Fatigue Performance ◽

Test Results ◽

Temperature Performance ◽

Cracking Performance ◽

Low Temperature Cracking ◽

Short And Long Term ◽

Analysis Of Performance

Sasobit warm mix drainage asphalt pavement has become increasingly popular due to its environmental benefits and comfortable using effect. However, test results show that its low-temperature and anti-fatigue performance have a certain degree of reduced. To improve the performance of asphalt four different doses (1%, 3%, 5% and 7%) of salt are added to the Sasobit asphalt. Laboratory tests were used to simulate short and long term aging asphalt in the process of construction and using pavement. A series of binder tests including bending beam rheometer (BBR), dynamic shear rheometer (DSR) and Brookfield viscosity tests were conducted. Results show an increase of rutting performance for warm mix binders with Sasobit while asphalt with salt has similar high temperature performance to original asphalt. Unlike Sasobit which has a decrease of cracking performance for asphalt at low-temperature, salinity can greatly improve the Low-temperature performance. And the low-temperature cracking performance and anti-fatigue performance presents a tendency of climbing up first and then declining with the increase of salinity. The figure of viscosity-temperature curve shows that the optimum of salinity is 5%.Further more, asphalt with Sasobit and salt can gain better performance and same mixing and compaction effect in lower 20°C than hot mix asphalt without it.

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Long-term performance of the Anammox process under low nitrogen sludge loading rate and moderate to low temperature

Biochemical Engineering Journal ◽

10.1016/j.bej.2016.02.004 ◽

2016 ◽

Vol 110 ◽

pp. 95-106 ◽

Cited By ~ 35

Author(s):

J.A. Sánchez Guillén ◽

C.M. Lopez Vazquez ◽

L.M. de Oliveira Cruz ◽

D. Brdjanovic ◽

J.B. van Lier

Keyword(s):

Low Temperature ◽

Loading Rate ◽

Long Term Performance ◽

Term Performance ◽

Low Nitrogen ◽

Anammox Process

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

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198196154500107 ◽

1996 ◽

Vol 1545 (1) ◽

pp. 50-58 ◽

Cited By ~ 5

Author(s):

Hannele K. Zubeck ◽

Ted S. Vinson

Keyword(s):

Thermal Stress ◽

Low Temperature ◽

Asphalt Concrete ◽

Probabilistic Model ◽

Deterministic Model ◽

Crack Spacing ◽

Test Results ◽

Concrete Mixtures ◽

Specimen Test ◽

Low Temperature Cracking

A deterministic model and a probabilistic model were developed to predict low-temperature crack spacing as a function of time using thermal stress restrained specimen test results, pavement thickness and bulk density, pavement restraint conditions, and air temperature. The effect of aging on pavement properties was incorporated in the models by predicting the field aging with long-term oven aging 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 probabilistic model is recommended for use in predicting the low-temperature cracking of asphalt concrete mixtures.

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