Quality Control of Recycled Aggregates Derived from Construction and Demolition Wastes

In 2007, over 24 million tons of Construction and Demolition (C&D) wastes were generated in Hong Kong. Since the local landfills will be saturated in about 6 years, it is important to find a viable way to reuse these waste materials as to alleviate the demand on public fill capacity. In order to tackle the problem, the Hong Kong government has set up a temporary recycling facility in Hong Kong in 2002 for producing different sizes of recycled aggregate for use in various construction materials. The Hong Kong Polytechnic University has been studying the feasible use of recycled aggregates in Hong Kong for a number of years. A substantial amount of experimental results on the properties of recycled aggregates and the effect of recycled aggregates on the properties of concrete and other construction products (e. G. Concrete blocks and granular sub-base) has been published. In this paper, the experience of Hong Kong in using recycled aggregates are summarized and a set of quality control guidelines proposed for governing the use of recycled aggregates in Hong Kong is introduced. The experience and guidelines may also be useful for the recycling of waste materials derived from the recent Sichuan earthquake in China.