With a lot of plot investigation,the traditional water recycling system in underground cave dwelling (UCD) is intensively discussed and its composition and layout are studied,coupled with its working mechanism,so as to explore its rationality and adaptability.

Introduce the anti-buoyancy design key point for furnace pit structure,mainly discuss the confirmation of waterproof location,water reduction coefficient,sub-coefficient of load of water buoyancy.

Being one important element in underground cave dwellings,the Kang not only contains rich traditional culture,but also perfectly combines with the cave dwellings either in structural construction or function.

Primitive earth-sheltered dwellings have not beam supports,and completely use a digging raw earth-arched system as self-support system.

However,the development of earth-sheltered dwelling was restricted by a lot of factors,falling in a difficult position of being discarded and forgotten.