摘要: |
This document presents guidance on how to use recycled aggregates in concrete, asphalt and as unbound fill materials in building and infrastructure projects in Qatar. There has been a great increase in the rate of construction in Qatar over the last decade and the rate is set to increase further in the run up to the World Cup in 2022. The boom in construction requires a sustainable supply of aggregates. To date, most aggregates for concrete and asphalt have been imported, as Qatar has very limited reserves of good quality aggregate. However, several potential sources of recycled aggregates are available, including construction, demolition and excavation waste, incinerator bottom ash and steel slag. The potential use of recycled aggregates was investigated in research project NPRP-4-188-2-061 funded by the Qatar National Research Foundation at Qatar Foundation. The work involved a review of international experience, laboratory testing, site trials, analysis and reporting and was characterised by close collaboration between government, regulators, industry, producers, academia and others. As a result of the work, a number of updates were made to the 2014 edition of the Qatar Construction Specification to enable greater use of recycled aggregates in a number of applications, including structural concrete. The properties, availability and potential for use of the various recycled aggregates are described, along with the results from site trials in buildings and road applications. The need for good quality control of production is emphasised. Suggestions are made for more general improvements in the management of construction, demolition and excavation waste in Qatar and areas where further work is required are identified. Recommendations were made for updating the Qatar National Development Strategy to support the government strategy for sustainable development with protection of the environment. The process that has been followed to enable the greater use of recycled aggregates in Qatar could be a model for other countries in the Gulf with similar issues. |