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Effect of bio-oil on low-intermediate temperature properties of organosolv lignin-bitumen
Published in Xianhua Chen, Jun Yang, Markus Oeser, Haopeng Wang, Functional Pavements, 2020
Y. Zhang, X. Liu, S. Ren, R. Jing, W. Gard, P. Apostolidis, S. Erkens, A. Skarpas
Bitumen is a complex petroleum-based material that is the most widely used binder for paving applications. However, considering the uncertainty in crude oil supply, alternative binders are encouraged to be used as a replacement of bituminous binders or bitumen modifiers. Especially, lignin, among others, has attracted considerable attention as a modifier (Xu et al., 2017, Su et al., 2018) or substitute (van Vliet et al., 2016) of bitumen. Lignin is one of the most abundant natural polymers on Earth, with the total amount of lignin present in the biosphere estimated to exceed 300 billion tons and with an annual increase of approximately 20 billion tons (Bruijnincx, 2016). Lignin can be found as well in co-products of timber production, or byproducts of paper and pulp industries. Thus, the utilization of lignin in binders specially designed for pavements may bring large economic benefits to sustainable development.
Possible future pavements, with an emphasis on recycling
Published in Maxwell Lay, John Metcalf, Kieran Sharp, Paving Our Ways, 2020
Maxwell Lay, Metcalf John, Sharp Kieran
McAdam was a strong advocate of recycling the stones found in any pavement he was replacing or constructing (Chapter 9). Recycling is now a common part of a general sustainability assessment of a new pavement, recognising its potential to provide a significant reduction in the energy, water and materials ‘footprint’ caused by the construction and operation of a pavement. Thus, recycled materials are increasingly being used in pavement construction, mainly combined with bitumen to produce asphalt.
Materials and testing
Published in Malcolm Copson, Peter Kendrick, Steve Beresford, Roadwork, 2019
Malcolm Copson, Peter Kendrick, Steve Beresford
Bitumen is produced from selected crude oils by the distillation of petroleum. The distillate is obtained by first heating to about 350°C under atmospheric pressure to drive off light fractions, e.g. gasoline, kerosene and gas oil.
Performance evaluation of asphalt binders modified with waste engine oil and various additives
Published in International Journal of Pavement Engineering, 2022
Shayan Abbas, Syed Bilal Ahmed Zaidi, Imtiaz Ahmed
Hot-mix Asphalt (HMA) has been used widely to construct flexible pavements. Around 90% of pavements are flexible due to asphalt roads’ strength, durability, and easy repair mechanisms. The binder used in HMA mixture is bitumen which is a viscoelastic material. It behaves as an elastic solid at low temperatures and as a viscous liquid at higher temperatures. The demand for bitumen has increased up to 700 million barrels annually (Hassan et al. 2019). Bitumen is a viscous dark brown non-crystalline material with good binding and adhesion properties. It’s an organic material consisting of hydrocarbons, typically comprising 15% carbon and 80% hydrogen and other elements, i.e. oxygen, sulfur, nitrogen, and small traces of various metals (Hassan et al. 2019). Bitumen is a petroleum product obtained from the fractional distillation of crude oil, a natural resource. Natural resources are depleting continuously, significantly impacting its price hike and environmental pollution. Asphalt binder has been modified with many modifiers to counter the problem of waste material management, depletion of natural resources, and improving the performance of conventional binder. Modified or alternative binders are both cost-effective and environmentally friendly (Ahmad et al. 2021).
Properties of bitumen modified by polyethylene and polyethylene glycol with different molecular weights
Published in International Journal of Pavement Engineering, 2022
Tian Xia, Xiang Chen, Jianhui Xu, Wenqiang Chen, Xinyue Huang, Youbing Li
Bitumen is widely used in pavement and road construction. Approximately 95% of 100Mt of bitumen produced worldwide every year is utilised as pavement material in the twenty-first century (Lesueur 2009). Bitumen is a complex mixture of mostly hydrocarbons whose structure is well described by the colloidal model: solid particles (the asphaltenes) with a radius of a few nanometres dispersed in an oily liquid matrix (the maltenes) (Lesueur 2009). The maltenes consist of resin, aromatics and saturates whose molecular weight and aromaticity decrease successively (Claudy et al. 1991). Bitumen has a low molecular weight and a wide distribution of molecular weight, which make it sensitive to temperature, exhibiting brittleness at low temperature and viscosity at high temperature. To enhance the performance of base bitumen, modification should be done prior to use. The most common one is to blend it with polymer, such as styrene–butadiene–styrene (SBS), ethyl vinyl acetate (EVA), polyethylene (PE), to produce polymer-modified bitumen (PMB) (Vasiljevic-Shikaleska et al. 2010, Zhu et al. 2014, Rossi et al. 2015, Padhan and Sreeram 2018).
Studying the effect of soft bitumen on the rheological properties of reclaimed PMB binder by using the DSR
Published in International Journal of Pavement Engineering, 2018
Gang Liu, Liping Li, Shaopeng Wu, Martin van de Ven
Although recycling asphalt with a high RA content up to 60% in the base layer is a common practice in Europe, recycling using RA containing residual polymer has not been thoroughly investigated. When a normal paving grade bitumen is used, the recycled bitumen can be mixed with a softer one to create a new asphalt mix. Polymer-modified bitumen had different rheological properties compared to paving grade bitumen both at normal and elevated temperatures. Therefore, recycling of RA with polymer-modified biumen (PMB) was a different story, and some questions had to be answered, like if it was still possible to reuse the RA with PMB based on the log penetration rule (Van den bergh and Van de ven 2009). The binder in the RA containing residual polymer may be extremely stiff, and it could be a challenge to ‘rejuvenate’ the old PMB to utilise its potential contribution to new asphalt (Liu et al.2015).