Increasing the Efficiency of Asphalt by Introducing Additives Containing Polyphosphoric Acid

Abstract:

Bitumen modified by polyphosphoric acid (PPA), as well as in combination with polymers and is widely used for production of road bitumen, which correspond to high standards. Therefore, the aim of this work is to study the influence of the properties of the polyphosphoric acid with different contents of phosphorous oxide (P₂O₅) and a derivative of them based additives esters of polyphosphoric acid and synthetic phospholipids DAD-KT, developed by "Selena".The influence of these additives on the change of adhesive, cohesive properties of bitumen, as well as on the properties of asphalt concrete to change of the limits of the crushing stress, water saturation and long waterproof. The use of additives had a positive effect on the adhesion of bitumen with mineral material. The index of cohesion increased with the addition of DAD-KT, more than 80%. This is due to the presence in its structure of the polymer.In connection with the increase of adhesion and cohesion of asphalts modified polyphosphoric acid, asphalt concrete prepared with these binders should be characterized by the increased values of water, heat and frost resistance and resistance to rutting.Study of the influence of additives on the physico-mechanical characteristics of asphalt concrete shows a positive effect on the properties of the latter. So the strength of asphalt concrete at 20 °C has risen on average by 10 % relative to the initial bitumen without additives, the strength at 50 °C by 15 %, the strength at 0 °C decreased by 8-12 %, the water saturation decreased by 30-40 %, indicating that the decrease in porosity of asphalt concrete and increase the durability of asphalt to seasonal temperature changes. In turn, the resistance increased by 5-8 % relative to the bitumen without additives. Long resistant with additives also increased which can be explained by the improvement of adhesion of bitumen with mineral materials of asphalt concrete. So the resistance after 15 days of the original bitumen and bitumen with additives decreased by 15 and an average 5 %, respectively, after 30 days at 25 and 7 % respectively. It can be concluded that in the modification of bitumen polyphosphoric acid, and in particular the addition of DAD-KT, there has been a significant improvement in the properties of bitumen and asphalt concrete. Therefore, it is possible to expect the improvement of the quality of the road pavement made of asphalt, with the use of additives containing polyphosphoric acid, in particular - DAD-KT.

• Periodical: Key Engineering Materials (Volume 677)
• Pages: 128-132
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.677.128
• Online since: January 2016
• Authors: Valentina V. Yadykina, Christina Pashkova*
• Keywords: Additives, Asphalt, Bitumen, Efficiency, Polyphosphoric Acid

References

[1] R. Maldonad. Polyphosphoric acid in the bitumen. Highways. 2011. №5. pp.77-79.

[2] S. -C. Huang, TF Turner, FP Miknis, KP Thomas. Long-Term Aging Characteristics of Polyphosphoric Acid-Modified Asphalts. In Transportation Research Record: Journal of the Transportation Research Board. No. 2051. Transportation Research Board of the National Academies. Washington. DC. 2008. pp.1-7.

DOI: 10.3141/2051-01

[3] Terry S. Arnold, Jack Youtcheff, Needham Susan P. Use of Phosphoric Acid as Modifier for Hot-Mix Asphalt,. Presented at the Polyphosphoric Acid Modification of Asphalt Binders. 2012. pp.40-51.

[4] Ho, S., L. Zanzotto, and D. MacLeod. Impact of Chemical Modification on Composition and Properties of Asphalt Binders. Proc., Canadian Technical Asphalt Association, Vol. 46. 2001. pp.153-170.

[5] C. Giavarini, D. Mastrofini, and M. Scarsella. Macrostructure and Rheological Properties of Chemically Modified Residues and Bitumens. Energy & Fuels, Vol. 14. 2000. pp.495-502.

DOI: 10.1021/ef9902045

[6] G. Baumgardner, J. -F. Masson, J. Hardee, and A. Menapace. Polyphosphoric Acid Modified Asphalt: Proposed Mechanisms. Journal of Association of Asphalt Paving Technologists, Vol. 74. 2005. pp.283-285.