A large amount of asphalt pavement waste is generated annually during road maintenance and rehabilitation works. The waste contains aggregate and bitumen which can be processed into reclaimed asphalt pavement (RAP) to produce new asphaltic concrete for road construction. This initiative helps to conserve the natural aggregates as well as the bitumen required to produce asphaltic concrete.

With the funding support from the government agency, Samwoh has conducted an in-depth research study to determine the optimal mix designs of asphaltic concrete containing RAP for different applications. After the successful completion of this research study, the company set up a state-of-the-art asphalt manufacturing plant with the capability to process asphalt pavement waste into RAP and to produce asphaltic concrete containing RAP.

Further to laboratory testing, a field trial was also carried out to assess the field performance of the asphaltic concrete containing RAP. This innovation spearheaded by Samwoh has resulted in the change of code of practices whereby RAP can be used up to 20% and 30% for the production of asphalt wearing course and asphalt binder course respectively in 2010.