Abstract: As a number of tunnels are constructed by means of shield machines in cities in China, shield muck has become the dominating urban construction waste, posing great challenges to urban environment. The status quo of shield muck reclamation, discharge hazards, disposal methods and problems, reclamation technologies and cases are summarized and analyzed, and then the problems to be solved and the development trend of shield muck disposal in the future are put forward. Specifically, (1) The utilization rate of construction waste in European developed countries and the United States is relatively high, while the reclamation rate of shield muck in China is roughly less than 1%. (2) China′s shield muck is currently disposed of in the conventional way of open piling or landfill, posing such hazards as occupying land, polluting soil and water, damaging urban landscape and environment and causing safety issues. (3) At present, China has basically developed shield muck reclamation processes or technologies such as using the muck as simultaneous grouting material, building product material, highstrength and highdensity ceramsite material and planting soil material. However, these technologies have not been scaled up due to technical level, economic cost, policy support and other factors. (4) China needs to make further breakthroughs in muck disposal and reclamation technologies. At the same time, the government should also give strong support in management mechanism and policy support to help dispose of shield muck in a "harmless, recyclable, standardized and industrialized" manner.

Key words: shield muck, treatment method, harmless disposal; reclamation