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Testing the parameters of hot-mix asphalt incorporating asphalt granulate

Jędrzejczyk Paula, Respondek Zbigniew

Budownictwo o Zoptymalizowanym Potencjale Energetycznym

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2024

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Vol. 13

15--22

EN

In recent years, the scale of use of recycled asphalt pavements for the production of hot mix asphalt (HMA) in Poland has been much smaller than in most other developed countries. Recently issued legal regulations and technical guidelines give hope for significant progres in this field. The article aims to investigate the parameters of HMA containing asphalt granulate (AG) in the context of using locally available materials and increasing the percentage of AG above the maximum amount recommended by current guidelines. It was found that the content of up to 40% AG used as an aggregate replacement does not significantly worsen the key parameters of HMA intended for the construction of an asphalt concrete subbase. The use of asphalt granulate may also result in a significant (up to approximately 50%) reduction in the consumption of road bitumen for the production of HMA

2

Preliminary study of hot mix asphalt containing water treatment and sewage sludge

Bastidas-Martínez J. G., Camapum de Carvalho J., Lucena L. C., Farias M. M., Rondón-Quintana H. A.

Archives of Civil Engineering

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2020

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Vol. 66, nr 1

225--240

EN

Throughout the world, considerable quantities of water treatment sludge (WTS) and sewage sludge (SS) are produced as waste. This study assessed in the laboratory, the possibility to use both waste products when they are incorporated as filler at 1% with relation to the total mass of a hot mix asphalt - HMA. To this end, both waste products were initially reduced to ash through a calcination process. Resistance tests under monotonic load (Marshall and indirect tension tests), and cyclic load (resilient modulus test) were applied on mixes that contained WTS and SS. Besides, moisture damage (modified Lotmman test), and abrasion (Cantabro) resistance were assessed. An analysis of variance (ANOVA) test was performed in order to verify if the results are statically equal or not to those of the control HMA. As a general conclusion, it is reported that both materials show a resistance increase under monotonic load and higher stiffness under cyclic load (cohesion) when they are incorporated into the mix as filler despite the fact that the asphalt content used was less than the control mix. However, some problems are observed associated with moisture damage resistance, and friction wear (adherence).

3

Evaluation of hot-mix asphalt containing Portland cement treated blast furnace slag

Rondón-Quintana H. A., Ruge-Cardenas J. C., Bastidas-Martínez J. G.

Archives of Civil Engineering

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2019

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Vol. 65, nr 2

193--207

EN

Iron production’s waste materials include significant quantities of blast furnace slag (BFS) which could potentially be used as a substitute for natural aggregates in hot mix asphalt (HMA) used in highway projects. Although many of properties of slag are interesting, its porosity and absorption rate would lead to greater consumption of asphalt. For this study, a Portland cement (PC) paste was used to reduce the porosity of a BFS. This PC treated BFS (called BFS-C) was then used in an HMA to replace the coarse fraction of a natural aggregate. Marshall, Indirect Tensile Strength (ITS), resilient modulus and Cantabro tests were then carried out on different HMA mixtures that included BFS-C. Using BFS-C, HMA’s resistance under monotonic loading, stiffness under cyclic loading, and resistance to moisture damage increased remarkably. In addition, the Cantabro abrasion resistance of BFS-C improved was better than that of the HMA mixture produced with untreated BFS.

4

Prediction of asphalt creep compliance using artificial neural networks

Zofka A., Yut I.

Archives of Civil Engineering

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2012

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Vol. 58, nr 2

153-173

EN

Creep compliance of the hot-mix asphalt (HMA) is a primary input of the current pavement thermal cracking prediction model used in the US. This paper discusses a process of training an Artificial Neural Network (ANN) to correlate the creep compliance values obtained from the Indirect Tension (IDT) with similar values obtained on small HMA beams from the Bending Beam Rheometer (BBR). In addition, ANNs are also trained to predict HMA creep compliance from the creep compliance of asphalt binder and vice versa using the BBR setup. All trained ANNs exhibited a very high correlation of 97 to 99 percent between predicted and measured values. The binder creep compliance functions built on the ANN-predicted discrete values also exhibited a good correlation when compared with the laboratory experiments. However, the simulation of trained ANNs on the independent dataset produced a significant deviation from the measured values which was most likely caused by the differences in material composition, such as aggregate type and gradation, presence of recycled additives, and binder type.