OJCE  Vol.7 No.2 , June 2017
Crumb Rubber Modified Bitumen in Open Graded Wearing Course of Flexible Pavement
Abstract: Rapid road infrastructure development due to an increasing demand of car users resulted in an increase in paved areas including road sites and suppression of green spaces. An integrated solution that can support a country’s economic development without compromising water pollution is becoming inevitable. Recycling tyres in the form of crumb rubber tyres and mixing it into bituminous paving mixture can increase the recycling rate and minimize cost of incineration process. In dry mixing process, five (5) different variations of Open Graded Wearing (OGW) course road samples were made to make up 1.15 kg in each sample. Each OGW mix contained 4% - 6% bitumen Pen 60/ 70 and fixed 1% of crumb rubber tyres, making the percentage of crumb rubber tyres 14% - 20% of bituminous samples. Bitumen Pen 60/70 mixed with 20% crumb rubber tyres content met the PG 76 bitumen properties. Physical properties of OGW made from crumb rubber modified bitumen (CRMB) were better than standard bitumen only. In a separate water leachate test using ICP-OES equipment, heavy metal leachate of Cu(II), Pb(II), Zn(II) and Cd(II) were present in all OGW CRMB samples at increasing surrounding water temperature from 25 to 60. However all the heavy metal concentration was very low below the allowable limit of trade effluent standards into water course.
Cite this paper: Lwin, M. and Utomo, H. (2017) Crumb Rubber Modified Bitumen in Open Graded Wearing Course of Flexible Pavement. Open Journal of Civil Engineering, 7, 165-176. doi: 10.4236/ojce.2017.72010.

[1] (2016) Waste Statistics and Overall Recycling.

[2]   Caltrans (2006) Asphalt Rubber Usage Guide. State of California Department of Transportation, Materials Engineering and Testing Services.

[3]   ASTM (2009) D6114/D6114M. American Society for Testing and Materials; Standard Specification for Asphalt-Rubber Binder.

[4]   Heitzman, M. (1992) Design and Construction of Asphalt Paving Materials with Crumb Rubber Modifier. Transportation Research Record 1339.

[5]   SAMWOH (2014)

[6]   Djati Utomo, H., Tan, K.X.D., Choong, Z.Y.D., Yu, J.J., Ong, J.J. and Lim, Z.B. (2016) Biosorption of Heavy Metal by Algae Biomass in Surface Water. Journal of Environmental Protection, 7, 1547-1560.

[7]   Land Transport Authority (2010) Materials and Workmanship Specifications for Civil & Structural Works (Revision A1, Jun 2010), Singapore.

[8]   Yero, S.A. and Hainin, M.R. (2012) Evaluation of Bitumen Properties Modified with Additives. IJRRAS, 13, 93-97.

[9]   Land Transport Authority (2012) Code of Practice for Works on Public Streets, Singapore.

[10] (2016) Allowable Limits for Trade Effluent Discharge to Sewer/Water- course/Controlled Watercourse.