With the development of urban infrastructure, more and more underground continuous wall is used as the retaining structure of foundation pit. A large amount of slurry is needed to protect the wall during the construction of underground continuous wall trench. The new slurry is used to protect the wall when the first underground continuous wall trench is formed, and the recycled slurry is used when the subsequent underground continuous wall trench is formed. The slurry is recycled after the cyclone desander is used to separate the large particle residue When the mud reaches the specific gravity of 1.3 and viscosity of more than 30s, it needs to be discarded.
Therefore, a large amount of waste mud will be produced in the construction of underground continuous wall. At present, the treatment of waste mud in the city is directly discharged into the sewage pipeline or transported to the surrounding of the city and dumped into the ditch or fish pond. Due to the high polymer material in the mud, the current treatment methods cause great pollution and damage to the environment, and the cost of mud transportation is very high.
1. Precast pile type or precast slab type continuous wall is widely used, which has smooth wall surface, good quality and high strength.
2. The technology of diaphragm wall is developing in the direction of large depth and high precision, and there are reports of diaphragm wall used in deep foundation construction of bridge abroad.
3. Polymer mud has been applied more and more. Compared with traditional bentonite mud, this kind of mud can reduce the amount of waste mud and increase the reuse times of mud.
4. Waste mud treatment technology has been widely used, some countries can achieve all the treatment after discharge.
