Feasibility study of using dredged marine deposits stabilised with coal fly ash as fill materials for geotechnical projects in Hong Kong

Professor Kwok, Chung Yee   (Principal Investigator (PI))

Professor Shih Kaimin   (Co-Investigator)

Mr Fong Hok Shing Michael   (Co-Investigator)

Dr Lee Daman   (Co-Investigator)

24

2021-07-02

490000

Feasibility study of using dredged marine deposits stabilised with coal fly ash as fill materials for geotechnical projects in Hong Kong

coal fly ash, dredged marine deposits, Feasibility, fill materials, geotechnical projects in Hong Kong, stabilised

Geotechnical

Engineering (E)

ECF Project 170/2020

Environment and Conservation Fund

2020

Completed

1. Dredged marine deposits, resulting from fairway maintenance and offshore excavation work, are a significant source of solid wastes in Hong Kong, with an average of 25 million tonnes annually. They are generally dumped in open waters, which is often a costly practice and may lead to adverse effects to the ecological environment. Exploring the reusability of the dredged marine deposits could minimize the need of dumping and meanwhile help relieve the shortage of fill materials that Hong Kong is facing. 2. Traditionally, cement is used for soft marine deposits stabilization. However, it is environmentally unfriendly to some extent, due to the greenhouse gas emission during the production of cement. Fly ash, a principle by-product of coal combustion for energy production, which is also a type of solid waste in Hong Kong. If the fly ash could be used to partially substitute cement for soil stabilization, it will undoubtably enhance the sustainability, considering both the cost and greenness.