DEVELOPING THE USE OF RECYCLED AND SECONDARY AGGREGATES IN QATAR

摘要

Recycled and secondary aggregates are widely used in construction in the UK and other developed countries but have not been used to a significant extent in hot desert countries. However the pressures of development in oil-rich regions such as the Gulf Coast, together with limited availability of high quality primary aggregate, are leading to greater interest in the use of recycled and secondary aggregates. This paper describes the situation in Qatar, a small state on the south shore of the Arabian Gulf. The current and future demand for aggregates is analysed and compared with the potential quantities of recycled and secondary aggregates available in the country. Large quantities of construction, demolition and excavation waste are available, with small quantities of incinerator bottom ash and steel slag. Very little of these materials is currently recycled, but they could make a significant contribution to the aggregate demand. A detailed programme of laboratory testing was carried out to assess the potential of the construction, demolition and excavation waste and incinerator bottom ash for use in unbound applications, structural and non-structural concrete and concrete blocks. The results are encouraging and a programme of site trials will now be carried out. If these are successful, the Qatar Construction Specification will be amended to enable the use of the materials.