Effect of asphalt binder oxidation on the modulus of asphalt concrete mixtures

The fine aggregate matrix (FAM) is an important constituent of an asphalt concrete mixture; the FAM is where some key damage phenomena such as cracking start and propagate. The proper design and fabrication of isolated FAM testing samples that are representative of the material existing within asphalt concrete mixtures requires the objective determination of key characteristics such as the apparent film thickness (FT) of the asphalt binder and the specific surface area of the aggregates. These relevant parameters facilitate the estimation of the binder content. This study presents an experimental testing and analysis protocol to determine the apparent FT that covers particles of fine aggregate in FAM mixtures. The method is based on tests using a scanning electron microscope and a digital image analysis procedure using the open-source Fiji/ImageJ software. The results indicated that apparent FT ranged between 0.5 µm and 30 µm. An additional validation effort was pursued and demonstrated the applicability of the proposed methodology, which can provide meaningful information to improve volumetric-based FAM mix design methods and generate materials that are more representative of those existing in the asphalt concrete mixtures.

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Evaluating the Role of Aggregate Gradation on Cracking Performance of Asphalt Concrete for Thin Overlays

Applied Sciences ◽

10.3390/app9040628 ◽

2019 ◽

Vol 9 (4) ◽

pp. 628 ◽

Cited By ~ 6

Author(s):

Lívia Garcia-Gil ◽

Rodrigo Miró ◽

Félix Pérez-Jiménez

Keyword(s):

Asphalt Concrete ◽

Material Selection ◽

Asphalt Binder ◽

Asphalt Mixture ◽

Fine Fraction ◽

Aggregate Size ◽

Aggregate Gradation ◽

Concrete Mixtures ◽

Cracking Performance

Thin asphalt concrete overlays are a maintenance technique that mainly restore the functional properties of pavements. One of the main issues in thin overlays is reflective cracking that can cause early deterioration and reduce their service life. For this reason, the purpose of this investigation is to evaluate the effect of material selection on cracking performance of asphalt concrete mixtures for thin overlays. In particular, this paper evaluates the role of aggregate skeleton gradation. The study of the effect of aggregate gradation was divided into two stages: (1) fine fraction content and (2) maximum nominal aggregate size. Based on this, up to seven asphalt mixture gradations were designed and evaluated through the Fénix test at different test temperatures. The results showed a significant correlation between the fine fraction content, and maximum nominal aggregate size, and the cracking performance of the asphalt concrete mixtures. Mixtures manufactured with a low content of fine aggregates, as well as small nominal maximum size, experienced a further improvement of their toughness. These results reflected the importance of considering not only the effect of asphalt binder and environmental conditions but also aggregate gradation in the design of asphalt concrete mixtures in order to achieve a desirable cracking performance.

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Assessing the Moisture and Aging Susceptibility of Cold Mix Asphalt Concrete

Journal of Engineering ◽

10.31026/j.eng.2021.02.05 ◽

2021 ◽

Vol 27 (2) ◽

pp. 59-72

Author(s):

Zahraa Ahmed Samor ◽

Saad Issa Sarsam

Keyword(s):

Tensile Strength ◽

Portland Cement ◽

Asphalt Concrete ◽

Ordinary Portland Cement ◽

Asphalt Binder ◽

Asphalt Mixture ◽

Hydrated Lime ◽

Technical Requirements ◽

Concrete Mixtures ◽

Age Related

Laboratory experience in Iraq with cold asphalt concrete mixtures is very limited. The design and use of cold mixed asphalt concrete had no technical requirements. In this study, two asphalt concrete mixtures used for the base course were prepared in the laboratory using conventional cold-mixing techniques to test cold asphalt mixture (CAM) against aging and moisture susceptibility. Cold asphalt mixtures specimens have been prepared in the lab with cutback and emulsion binders, different fillers, and curing times. Based on the Marshal test result, the cutback proportion was selected with the filler, also based on the Marshal test emulsion. The first mixture was medium setting cationic emulsion (MSCE) as a binder, hydrated lime, and ordinary portland cement as a filler (7.95% MSCE + 2%HL + 3% OPC). The second mixture used was medium curing cutback (MC-250) as a binder and ordinary portland cement as a filler (5.18% MC 250 + 5% OPC). The indirect tensile strength (ITS) of the samples was measured at 25 ° C. It was found that the cold mix with the MSCE binder had a high ITS value relative to the cold mix with the cutback asphalt binder (MC-250). The dry mixture of MSCE ITS was approximately 3.77 times the dry mixture of MC-250. The MSCE wet mix was about 4.2 times the wet MC-250 mix. Tensile strength ratio result (TSR %) for the MSCE binder mix and the cutback MC-250 binder mix showed that the MSCE mix has a reasonable moisture resistance (77% ) compared to the MC-250 mix (69.2 %). The aging test and aging ratio result showed that asphalt binder oxidation has a significant effect on age-related pavement degradation as it changes the time-temperature relationship depending on the viscoelastic properties of the asphalt binder. The result clearly showed that the MSCE binder mix had a high resistance to aging (440 Kpa) compared to the cutback (MC-250) binder mix (110 Kpa). In contrast, the MSCE aging ratio (90 %) was higher than the MC-250 ratio (85 %).

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PENELITIAN PENAMBAHAN BAHAN BATU PADAS PADA CAMPURAN ASPAL BETON

Jurnal Manajemen Teknologi & Teknik Sipil ◽

10.30737/jurmateks.v2i1.407 ◽

2019 ◽

Vol 2 (1) ◽

pp. 154

Author(s):

Supriadi Supriadi ◽

Yosef Cahyo ◽

Ahmad Ridwan ◽

Agata Iwan Candra

Keyword(s):

Compressive Strength ◽

Asphalt Concrete ◽

Coarse Aggregate ◽

Asphalt Binder ◽

Strong Stability ◽

Average Height ◽

Optimum Level ◽

Fine Aggregate ◽

Concrete Mixtures ◽

Technical Specifications

Asphalt Concrete (Hotmix) is a mixture of coarse aggregate, fine aggregate and filler (Filler) with asphalt binder in high temperature conditions with the composition studied and regulated by technical specifications. In this study, asphalt concrete mixtures were given materials additional padas. This addition was carried out to study and determine the effect of padas on the asphalt concrete mixture with the addition of 5%, 10%, and 15%. Compressive strength specimens in the form of cylinders with a diameter of 10.09 cm and an average height of 7.8 cm. Testing is done after 2 days. Asphalt with the addition of 5% padas is better able to produce a better value of stability than others. The addition of padas rock produced a strong stability of 5% at 888.0747 kg, 10% at 598,199 kg, 15% at 441,6391 kg. To reach the optimum level, the mixture on concrete asphalt ranges < 5%Aspal Beton (Hotmix) adalah campuran agregat kasar, agregat halus, dan bahan pengisi (Filler) dengan bahan pengikat aspal dalam kondisi suhu tinggi (panas) dengan komposisi yang diteliti dan diatur oleh spesifikasi teknis.. Pada penelitian ini, campuran aspal beton diberi bahan tambahan batu padas. Penambahan ini dilakukan untuk mempelajari dan mengetahui pengaruh batu padas pada campuran aspal beton dengan penambahan 5%, 10%, dan 15%. Benda uji kuat tekan berupa silinder dengan diameter 10,09 cm dan tinggi rata rata 7,8 cm. Pengujian dilakukan setelah 2 hari. Aspal dengan penambahan batu padas 5% lebih mampu menghasilkan nilai stabilitas yang lebih baik dari pada yang lainya. Penambahan batu padas menghasilakan kuat stabilitas masing masing yaitu 5% sebesar 888.0747 kg, 10% sebesar 598.199 kg, 15% sebesar 441.6391 kg. Untuk mencapai kadar optimum maka campuran padas pada aspal beton berkisar antara < 5%

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Structured asphalt binder is a new binder type in asphalt concrete mixtures

Russian journal of transport engineering ◽

10.15862/08sats321 ◽

2021 ◽

Vol 8 (3) ◽

Author(s):

Denis Gerasimov ◽

Aleksey Ignatev ◽

Valery Gotovtsev

Keyword(s):

Asphalt Concrete ◽

Water Saturation ◽

Asphalt Binder ◽

Experimental Studies ◽

Technical Performance ◽

Concrete Mixtures ◽

Binder Type ◽

Powder Particles ◽

Mineral Powder ◽

Time Changes

The data presented in the article are part of disserta-tion research on the formula development and pro-duction principle of composite material for road con-struction with phosphogypsum and secondary poly-ethyleneterephthalate use. The article provides an assessment of the existing most successful and effec-tive technologies for creating asphalt concrete pave-ments with high technical performance characteris-tics, and the key role in formula is an asphalt binder on the binary system mineral powder/oil road bitu-men basement, their main advantages and disad-vantages are described. A new technological method for the asphalt concrete mixtures production is de-scribed - pelletization by rolling, which was proposed by the authors. The paper presents the study's results to determine the structured asphalt binder technical and operational properties obtained by the method of pelletization by rolling. A brief theoretical substantia-tion of the physicochemical nature of improving a number of developed composition technical and op-erational characteristics of a structured asphalt binder is presented. The dynamics of over time changes in the main structured asphalt binder indicators, from 2005 to 2019, are given. It has been theoretically proven that in a structured asphalt binder obtained by the method of pelletization by rolling, bitumen is in a film state, and the bitumen interlayers thickness be-tween the mineral powder particles is of the order of 100 nm, which makes it possible to classify the prod-uct as a nanomaterial and determines its special properties set. The data of independent and our own experimental studies are also presented, indicating the previously obtained theoretical justification correct-ness for increasing the strength indicators, improving the water saturation indicators, and the water re-sistance coefficient. The absence of negative changes in the main technical and operational properties dy-namics for 14 years confirms the possibility of storing the mixture in a cold form outside a sealed package in an unheated room, which makes it possible to assert the possibility of preparing material for future use and transporting it over unlimited distances.

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Structured asphalt binder is a new binder type in asphalt concrete mixtures

Russian journal of transport engineering ◽

10.15862/07sats321 ◽

2021 ◽

Vol 8 (3) ◽

Author(s):

Denis Gerasimov ◽

Aleksey Ignatev ◽

Valery Gotovtsev

Keyword(s):

Asphalt Concrete ◽

Water Saturation ◽

Asphalt Binder ◽

Experimental Studies ◽

Technical Performance ◽

Concrete Mixtures ◽

Binder Type ◽

Powder Particles ◽

Mineral Powder ◽

Time Changes

The data presented in the article are part of disserta-tion research on the formula development and pro-duction principle of composite material for road con-struction with phosphogypsum and secondary poly-ethyleneterephthalate use. The article provides an assessment of the existing most successful and effec-tive technologies for creating asphalt concrete pave-ments with high technical performance characteris-tics, and the key role in formula is an asphalt binder on the binary system mineral powder/oil road bitu-men basement, their main advantages and disad-vantages are described. A new technological method for the asphalt concrete mixtures production is de-scribed - pelletization by rolling, which was proposed by the authors. The paper presents the study's results to determine the structured asphalt binder technical and operational properties obtained by the method of pelletization by rolling. A brief theoretical substantia-tion of the physicochemical nature of improving a number of developed composition technical and op-erational characteristics of a structured asphalt binder is presented. The dynamics of over time changes in the main structured asphalt binder indicators, from 2005 to 2019, are given. It has been theoretically proven that in a structured asphalt binder obtained by the method of pelletization by rolling, bitumen is in a film state, and the bitumen interlayers thickness be-tween the mineral powder particles is of the order of 100 nm, which makes it possible to classify the prod-uct as a nanomaterial and determines its special properties set. The data of independent and our own experimental studies are also presented, indicating the previously obtained theoretical justification correct-ness for increasing the strength indicators, improving the water saturation indicators, and the water re-sistance coefficient. The absence of negative changes in the main technical and operational properties dy-namics for 14 years confirms the possibility of storing the mixture in a cold form outside a sealed package in an unheated room, which makes it possible to assert the possibility of preparing material for future use and transporting it over unlimited distances

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