Laboratory Evaluation of Recycled Pavement Materials Stabilized with Nano Polymer

DOI: 10.5176/2301-394X_ACE14.26

Authors: Mhlongo, S.M., Ndambuki, J.M., Kupolati, W.K., Abiola, O.S

Abstract:

The paper dealt with the laboratory evaluation of the recycled pavement materials stabilized with SoilTech Mk lll Nano polymer, which uses water as a carrier to lubricate the fine particles at molecular level that gets interlocked under mechanical compaction. Sampling was carried out in line with specifications. The samples cored shown a three layer pavement. Sub-base and base materials were collected from the rehabilitated pavement in Mpumalanga Province, South Africa. Laboratory tests were conducted to determine the mechanical properties, optimum moisture content (OMC), maximum dry density (MDD) and California bearing ratio (CBR) of the pavement materials in accordance with the South African road specifications and American Society for Testing Materials (ASTM). The plasticity index (PI), OMC and CBR of the sub base and base are: 15, 10; 7.04{6e6090cdd558c53a8bc18225ef4499fead9160abd3419ad4f137e902b483c465}, 5.3{6e6090cdd558c53a8bc18225ef4499fead9160abd3419ad4f137e902b483c465}; and 52{6e6090cdd558c53a8bc18225ef4499fead9160abd3419ad4f137e902b483c465}, 34{6e6090cdd558c53a8bc18225ef4499fead9160abd3419ad4f137e902b483c465} respectively. The specification states that if PI > 6 such materials should be stabilized. Sub-base and base materials were mixed with 0, 0.5, 0.8 and 1.0{6e6090cdd558c53a8bc18225ef4499fead9160abd3419ad4f137e902b483c465} SoilTech polymer at OMC and MDD. The stabilized materials were examined for Unconfined Compressive Strength (UCS) test in line with specification at 14-day of curing. The results showed an increase in strength at 0.5{6e6090cdd558c53a8bc18225ef4499fead9160abd3419ad4f137e902b483c465} polymer of 76{6e6090cdd558c53a8bc18225ef4499fead9160abd3419ad4f137e902b483c465}, 86{6e6090cdd558c53a8bc18225ef4499fead9160abd3419ad4f137e902b483c465} for sub base and base respectively of their original strength. Addition of the polymer results in further increase in strength. For optimum and cost effectiveness in terms of the polymer, 0.5{6e6090cdd558c53a8bc18225ef4499fead9160abd3419ad4f137e902b483c465} polymer met the requirement for design. It can be concluded that the polymer improved the UCS values of the pavement materials.

Keywords: SoilTech polymer; improvement; pavement materials; unconfined compressive strength; stabilized