dougong is a system of brackets in chinese building：wooden square blocks inserted between the top of a column and a crossbeam
DouGong (Bucket Arch) brackets are extremely versatile , they have been used throughout the architecture for literally thousands of years, they reached their zenith in the Forbidden City, there are no nails or glue, nothing holding it together, other than sheer ingenuity, it is very strong, pressing down it can take a tremendous amount of weight, it ties together with other parts of the building and it is a beautiful creative feature of Chinese architecture.
the complicated dougong brackets extend to the exterior to support the eaves as well as the roof, they sit on the large beams, supported by the tall columns, but the columns are not founded in the earth and are free-standing, all these structural parts bear the roof's immense weight.
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