A review of Hong Kong’s current aggregate supply for concrete production and possibility of using aggregate processed from excavated rock from construction sites to manufacture concrete

Abstract

As one of the existing quarries in Hong Kong i.e. Anderson Road Quarry has been recently closed for rehabilitation, Lam Tei Quarry is the only remaining quarry in Hong Kong for local production of aggregate for concrete. As a result, the local construction industry is now heavily relying on the imported aggregate from mainland China. However, insecure supply of aggregate will be a potential risk as the local demand on aggregate is also strong in mainland China due to its rapid infrastructure development. Therefore, it is essential to look for alternative local supply of aggregate for concrete to copy with the continuous strong construction development in Hong Kong in the future. This dissertation looks at possibility, primarily from technical point of view, to recycle the excavated rock from construction projects to produce aggregate for concrete production. By comparing the desired aggregate properties for concrete production with the aggregate properties of Hong Kong rocks, the technical feasibility to recycling the excavated rock from construction sites to produce aggregate for concrete production will be concluded. Moreover, based on personal site experience working with the main contractors, practical site control measures to improve the quality of excavated rock for aggregate production are proposed to encourage the contractors of construction projects to take the initiative to implement the recycling practice.