Ageing and temperature effect on the fatigue performance of bituminous mixtures

The ageing of asphalt mixes, together with their exposure to low temperatures, causes a progressive increase of cracking. In this paper, the effect of ageing and temperature on the fatigue of asphalt concretes made with two types of binders, conventional (50/70) and polymer modified bitumen (PMB), is studied. For this purpose, specimens previously subjected to an accelerated laboratory ageing process were tested by a strain sweep test at different temperatures (-5ºC, 5ºC and 20°C). Results were compared with the obtained from the unaged specimens showing the relative importance of ageing, temperature and type of bitumen on the parameters that determine the fatigue life of the mixture. The mixtures behaviour becomes more brittle with ageing and the decrease of temperature. However, ageing hardly has an effect on fatigue at lower temperatures. In general, mixtures made with polymer modified bitumen have a better fatigue performance to ageing and temperature.

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Evaluation Of Volumetric Properties And Resilient Modulus Performance Of Nanopolyacrylate Polymer Modified Binder (NPMB) Asphalt Mixes

Jurnal Teknologi ◽

10.11113/jt.v73.4280 ◽

2015 ◽

Vol 73 (4) ◽

Author(s):

Ekarizan Shaffie ◽

Juraidah Ahmad ◽

Ahmad Kamil Arshad ◽

Dzraini Kamarun

Keyword(s):

Resilient Modulus ◽

Asphalt Mixture ◽

Asphalt Mixtures ◽

Volumetric Properties ◽

Modified Bitumen ◽

Asphalt Mixes ◽

Different Types ◽

Potential Benefits ◽

Modified Binder ◽

Polymer Modified Bitumen

This paper presents the potential benefits of nanopolyacrylate (NPA) for the asphalt mixtures used on pavement. This research evaluates the resilient modulus performance of dense graded Superpave-designed HMA mix. Two different types of dense graded Superpave HMA mix were developed consists of unmodified bitumen mix (UMB) and nanopolyacrylate modified bitumen mix (NPMB). Nanopolyacrylate polymer modified bitumen was prepared from addition of 6 percent of NPA polymer into asphalt bitumen. Resilient modulus results from Resilient Modulus test were determined to evaluate the performance of these mixtures. Results showed that all the mixes passed the Superpave volumetric properties criteria which indicated that these mixtures were good with respect to durability and flexibility. The Resilient modulus result of NPMB demonstrates better resistance to rutting than those prepared using UMB mix. It was estimated that the average resilient modulus values for both UMB and NPMB mixtures are decreased by 80 percent when the test temperature increased from 25ºC to 40ºC. In conclusion, the addition of NPA to the binder has certainly improved the bitumen properties significantly and hence increase the resistant to rutting of the asphalt mixture.

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Rheological Evaluation of Modified Bitumen by EVA and Crumb Rubber Using RSM Optimization

Advances in Materials Science and Engineering ◽

10.1155/2021/9825541 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Mohamad H. Dehnad ◽

Behrouz Damyar ◽

Hossein Z. Farahani

Keyword(s):

Low Temperatures ◽

Ethylene Vinyl Acetate ◽

Crumb Rubber ◽

Test Results ◽

Modified Bitumen ◽

Rsm Optimization ◽

Different Temperatures ◽

Creep Stiffness ◽

Optimal Values ◽

High And Low Temperatures

In the present study, ethylene-vinyl acetate (EVA) and crumb rubber (CR) were used as bitumen modifiers. The experiment was designed by response surface methodology (RSM) at different levels of modifier additives based on the central composite design (CCD). Next, the Superpave protocol was followed to evaluate the modified bitumen performance at different temperatures compared with the unmodified bitumen. In this regard, to evaluate at high temperatures, a dynamic shear rheometer (DSR) test was performed, and G ∗ /sinδ index was examined on bitumen samples after aging. Besides, the bending beam rheometer (BBR) test was performed to evaluate the low-temperature behaviour of the modified bitumen according to the SHRP standard based on the creep stiffness and creep rate. The optimal combination of additives was evaluated using RSM and analysis of statistical values to improve the performance properties of bitumen at high and low temperatures. Moreover, based on the DSR and BBR test results, 5.6% of EVA and 3.9% of CR were selected as the optimal values for the modified bitumen behaviour at the high and low temperatures of the mixture.

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LABORATORY INVESTIGATION INTO THE EFFECTS OF FIBERS ON BITUMINOUS MIXTURES

Journal of Civil Engineering and Management ◽

10.3846/13923730.2013.802720 ◽

2014 ◽

Vol 21 (1) ◽

pp. 45-53 ◽

Cited By ~ 8

Author(s):

Emanuele Toraldo ◽

Edoardo Mariani ◽

Sara Malvicini

Keyword(s):

Mechanical Performance ◽

Road Construction ◽

Modified Bitumen ◽

Research Project ◽

Bituminous Mixtures ◽

Different Types ◽

Road Materials ◽

Compaction Properties ◽

Polymer Modified Bitumen ◽

Bitumen Modification

The growing need for high quality bituminous mixtures in road construction, rehabilitation and maintenance is currently satisfied by means of techniques to produce polymer-modified bitumen, or by the addition of additives to mixtures during in-plant mixing operations. A rigorous rheological approach in the study of the bitumen modification process enables researchers to rationally compare different modifying agents and to evaluate their relative efficiency for specific field applications. As far as additives are concerned, the binder is not the only element involved in the evaluation; both binding mastics and bituminous mixtures must be evaluated to get a complete understanding of the characteristics. Moreover, the advantages that may stem from the use of fibers should be carefully taken into consideration since they may offer alternative strategies for the enhancement of bituminous mixtures. As a result of these observations, the authors have devised an experimental research project focused on the analysis of the effects of different types and dosages of cellulose-based fibers on the main performance-related properties of bituminous road materials: compaction properties, volumetric characteristics and mechanical performance. This paper provides an overview of the results obtained and some details of the specific protocols followed during the research project.

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Analysis of the Effects of Ageing on the Cohesive Strength of Polymer-Modified Bitumen at Low Temperatures

The Baltic Journal of Road and Bridge Engineering ◽

10.7250/bjrbe.2018-13.410 ◽

2018 ◽

Vol 13 (2) ◽

pp. 156-164 ◽

Cited By ~ 1

Author(s):

Chuanfeng Zheng ◽

Genze Li ◽

Yazhi Xu ◽

Danni Wang ◽

Dan Lv

Keyword(s):

Low Temperature ◽

Low Temperatures ◽

Decay Curve ◽

Ageing Time ◽

Cohesive Strength ◽

Modified Bitumen ◽

Styrene Butadiene Styrene ◽

Styrene Butadiene ◽

Polymer Modified Bitumen ◽

Butadiene Styrene

The decay law on the ageing process of the cohesive strength of styrene-butadiene-styrene(SBS)- and polyethylene(PE)-modified bitumens at low temperatures was investigated. The rotated-thin-film oven test was used to age the two types of polymer-modified bitumens. The cohesive strengths at different low-temperature conditions were tested quantitatively according to technology for testing the low-temperature cohesive strength of bitumen. The decay curve of bitumen low-temperature cohesive strengths was drawn, and the embrittlement time of bitumen at different ageing states was obtained according to the decay curve. Results showed that ageing time definitely influenced the attenuation degree of the low-temperature cohesive strength of the two types of polymer-modified bitumens and influenced the appearance of the low-temperature cohesive strength peak, i.e., the bitumen embrittlement time, which advanced after ageing. The lightweight components of polymer-modified bitumen were lost after ageing. The bitumen embrittlement time was advanced, and the sharp attenuation of the low-temperature cohesive strength of bitumen appeared. In the future, bitumen antiageing technology and lighter part pre-supplement technology should be studied in-depth.

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Methods of test for petroleum and its products. BS2000-518. Bitumen and bituminous binders. Visualisation of polymer dispersion in polymer modified bitumen

10.3403/02964230u ◽

2015 ◽

Keyword(s):

Polymer Dispersion ◽

Modified Bitumen ◽

Bituminous Binders ◽

Polymer Modified Bitumen

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A Comparative Electrochemical and Morphological Investigation on the Behavior of NiCr and CoCr Dental Alloys at Various Temperatures

Metals ◽

10.3390/met11020256 ◽

2021 ◽

Vol 11 (2) ◽

pp. 256

Author(s):

Florentina Golgovici ◽

Mariana Prodana ◽

Florentina Gina Ionascu ◽

Ioana Demetrescu

Keyword(s):

Low Temperatures ◽

Artificial Saliva ◽

Electrochemical Stability ◽

Morphological Investigation ◽

Dental Alloys ◽

Ion Release ◽

Icp Ms ◽

Different Temperatures ◽

Good Concordance ◽

Increasing Temperature

The purpose of our study is to compare the behavior of two reprocessed dental alloys (NiCr and CoCr) at different temperatures considering the idea that food and drinks in the oral cavity create various compositions at different pH levels; the novelty is the investigation of temperature effect on corrosion parameters and ion release of dental alloys. Electrochemical stability was studied together with morphology, elemental composition and ions release determination. The results obtained are in good concordance: electrochemistry studies reveal that the corrosion rate is increasing by increasing the temperature. From SEM coupled with EDS, the oxide film formed on the surface of the alloys is stable at low temperatures and a trend to break after 310K. ICP-MS results evidence that in accordance with increasing temperature, the quantities of ions released from the alloys immersed in artificial saliva also increase, though they still remain small, less than 20 ppm.

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Multi-Criteria Selection of Additives in Porous Asphalt Mixtures Using Mechanical, Hydraulic, Economic, and Environmental Indicators

Sustainability ◽

10.3390/su13042146 ◽

2021 ◽

Vol 13 (4) ◽

pp. 2146

Author(s):

Anik Gupta ◽

Carlos J. Slebi-Acevedo ◽

Esther Lizasoain-Arteaga ◽

Jorge Rodriguez-Hernandez ◽

Daniel Castro-Fresno

Keyword(s):

Cellulose Fiber ◽

Environmental Indicators ◽

Asphalt Mixtures ◽

Environmental Benefits ◽

Modified Bitumen ◽

Porous Asphalt ◽

Different Types ◽

Product Assessment ◽

Polymer Modified Bitumen ◽

Selection Of

Porous asphalt (PA) mixtures are more environmentally friendly but have lower durability than dense-graded mixtures. Additives can be incorporated into PA mixtures to enhance their mechanical strength; however, they may compromise the hydraulic characteristics, increase the total cost of pavement, and negatively affect the environment. In this paper, PA mixtures were produced with 5 different types of additives including 4 fibers and 1 filler. Their performances were compared with the reference mixtures containing virgin bitumen and polymer-modified bitumen. The performance of all mixes was assessed using: mechanical, hydraulic, economic, and environmental indicators. Then, the Delphi method was applied to compute the relative weights for the parameters in multi-criteria decision-making methods. Evaluation based on distance from average solution (EDAS), technique for order of the preference by similarity to ideal solution (TOPSIS), and weighted aggregated sum product assessment (WASPAS) were employed to rank the additives. According to the results obtained, aramid pulp displayed comparable and, for some parameters such as abrasion resistance, even better performance than polymer-modified bitumen, whereas cellulose fiber demonstrated the best performance regarding sustainability, due to economic and environmental benefits.

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Mechanical Characteristics of Graphene Nanoplatelets-Modified Asphalt Mixes: A Comparison with Polymer- and Not-Modified Asphalt Mixes

Materials ◽

10.3390/ma14092434 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2434

Author(s):

Laura Moretti ◽

Nico Fabrizi ◽

Nicola Fiore ◽

Antonio D’Andrea

Keyword(s):

Fatigue Resistance ◽

Graphene Nanoplatelets ◽

Asphalt Mixtures ◽

Asphalt Binders ◽

Asphalt Mixes ◽

Modified Asphalt ◽

Bituminous Mixtures ◽

Water Sensitivity ◽

Polymer Modified Asphalt ◽

Mechanical Performances

In recent years, nanotechnology has sparked an interest in nanomodification of bituminous materials to increase the viscosity of asphalt binders and improves the rutting and fatigue resistance of asphalt mixtures. This paper presents the experimental results of laboratory tests on bituminous mixtures laid on a 1052 m-long test section built in Rome, Italy. Four asphalt mixtures for wearing and binder layer were considered: two polymer modified asphalt concretes (the former modified with the additive Superplast and the latter modified with styrene–butadiene–styrene), a “hard” graphene nanoplatelets (GNPs) modified asphalt concrete and a not-modified mixture. The indirect tensile strength, water sensitivity, stiffness modulus, and fatigue resistance of the mixtures were tested and compared. A statistical analysis based on the results has shown that the mixtures with GNPs have higher mechanical performances than the others: GNP could significantly improve the tested mechanical performances; further studies will be carried out to investigate its effect on rutting and skid resistance.

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