Pavement construction and monitoring at Tampines Road
Collaborator(s):
Land Transport Authority & National Environment Agency
Project Completion:
Feb 2009
Objective(s):
- To process the incinerator bottom ash (IBA) into the engineered aggregates
- To evaluate the processed IBA for conformity in road construction
- To assess and monitor the field performance of processed IBA in the underlying road layers
Every year, about 500,000 tonnes of incinerator bottom ash (IBA) produced from the incineration of municipal solid waste is disposed at the only landfill in Singapore, Pulau Semakau. The disposal of IBA poses environmental problems due to limited landfill space in Singapore.
In view of this concern, Samwoh, Land Transport Authority (LTA) and National Environment Agency have jointly undertaken a research study to process IBA into the engineered aggregate for road construction. In this study, a pilot plant was set up to process IBA using a U.S. patented system. Extensive laboratory tests were carried out to assess the environmental and engineering properties of processed IBA. The laboratory test results showed that the processed IBA complied with the technical specifications for road construction. Further to the laboratory testing, a field trial was carried out at Tampines Road to evaluate the structural and environmental performance of the processed IBA with respect to the regulatory requirements. The performance was assessed using state-of-the-art pavement testing equipment and groundwater samples were also collected to determine the quality of groundwater over a period of time. Following the success of the trial, LTA has approved the use of processed IBA for road base construction in 2010.