Polyampholyte polymer as a stabiliser for subgrade soil

Ana K. Rodriguez, Chandramohan Ayyavu, Srinath Iyengar, Hassan S. Bazzi, Eyad Masad, Dallas Little, Howard J M Hanley

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8 Citations (Scopus)


This study evaluates the potential of selected ionic polymers to act as pavement subgrade binders. Investigations were based on their relative performance with a Qatari soil which was selected as typical of a pavement subgrade to be found in the Middle East and North African region. The polymeric binders chosen were three synthetic ionic variations of polyacrylamide: cationic poly(acrylamidopropyl trimethyl ammonium chloride) (designated PAMTAC), anionic hydrolysed poly(acrylamide) (HPAM) and the ampholitic terpolymer poly(acrylamide-co-sodiumacrylate-co-(3-acrylamidopropyl) trimethylammonium chloride) (TPAM). The polymers were characterised by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic spectroscopy (1H-NMR and 13C-NMR). The comparative performance of the polymer-treated soil was judged on the basis of results obtained from selected standard mechanical test data: specifically, the unconfined compressed strength, the stiffness modulus and the toughness. It is concluded that a 50% w/w aqueous solution of the ampholitic terpolymer applied at a dosage of 2.0% by dry weight of the soil gives the best subgrade stabilisation. Of some significance, it is further noted that this ampholitic polymer was superior as a binding agent to the traditional standard, Portland cement, judged under equivalent but nonstandard conditions. Modifying the polymer to act as a binder for subgrade soils in general is also discussed.

Original languageEnglish
Pages (from-to)1-12
Number of pages12
JournalInternational Journal of Pavement Engineering
Publication statusAccepted/In press - 22 Apr 2016



  • polyampholyte polymer
  • polymer stabiliser
  • Qatar
  • soil stabilisation
  • spectroscopy
  • Subgrade

ASJC Scopus subject areas

  • Civil and Structural Engineering
  • Mechanics of Materials

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