Building ZJ refers to column foundation. Generally, the shape of independent column foundation has the ZJ of pile cap, which is the foundation of column. ZJ- 1 is the type of pile foundation, ZJ is the initials of "pile" and "foundation", and 18- 18 is the specific size of the combined drawings. When the column foundation cannot bear the upper load, it is necessary to add piles, which is called pile foundation. This foundation can take many forms.

According to the drawing standard of building structure, when drawing drawings, they can be represented by capitalized Chinese pinyin initials, such as: Z stands for column; J stands for foundation; WB stands for roof panel; WL stands for roof beam; KJ stands for framework; LL stands for connecting beam; CT stands for capAZ, hidden column and so on.