Elimination of loess collapsibility with application to construction and demolition waste during dynamic compaction

With the rapid modernization of China's infrastructure construction, disposal of the massive amount of construction and demolition waste (CDW) produced each year has gradually developed into a national concern due to its increasingly adverse effect on the environment. Additionally, in northwestern China, ground deformation triggered by collapsible loess has caused severe damage to local infrastructure. In an attempt to address both problems simultaneously, this paper proposes the novel approach of applying CDW as a pile filler for the down-hole dynamic compaction. The concept, construction process, and design principles of this new method are described, and its efficiency and feasibility are validated in detailed studies of four practical cases in different locations in China. Problems that arise in certain aspects of this method, i.e., code revision with consideration of the variable loess conditions and CDW in different locations, are also discussed. Case studies and relevant discussions indicate a promising future for this environmentally friendly and eco-efficient method that is broadly applicable in many locations.