Optimisation of Marshall Design criteria with central composite design in asphalt concrete

Yildirim Z. B., KARACASU M., OKUR D. V.

INTERNATIONAL JOURNAL OF PAVEMENT ENGINEERING, vol.21, no.5, pp.666-676, 2020 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 21 Issue: 5
  • Publication Date: 2020
  • Doi Number: 10.1080/10298436.2018.1502439
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Communication Abstracts, Compendex, INSPEC, Metadex, Civil Engineering Abstracts
  • Page Numbers: pp.666-676
  • Keywords: Asphalt concrete, modelling, Marshall Design, central composite design, optimisation, FLOTATION
  • Eskisehir Osmangazi University Affiliated: Yes


In this study, optimum bitumen content (OBC), an important parameter on Marshall Design is described with a mathematical model by using statistical design method. The effects of independent variables such as number of blows, temperature, additive rate and bitumen content are analysed. The simultaneous optimisation of the dependent variables such as practical specific gravity, voids, voids of filled with asphalt cement, Marshall stability, flow and Marshall coefficient is determined with the central composite design. The optimum conditions are detected with 70 blows, temperature of 160 degrees C, additive amount of 10% and OBC of 4.484%. The desirability function is applied to determine local optimisation points. Following the model application, practical specific gravity is estimated to be 2.418 g/cm(3)with voids of 4%, voids of filled asphalt of 71.74%, Marshall stability of 1138.4 kgf under optimum conditions. While it is necessary to pour 126 samples to achieve a result with these variables in Marshall Design under normal conditions, the results are achieved just by pouring 30 samples thanks to the models established.