Design calculation consists of a design drawing and a structural calculation.

For tower crane or any machine installation requiring a supporting structure, there must be a design calculation for this structure to be submitted to the governing authority for approval.  Such a structure includes (i) foundation for the machine, (ii) wall tie support (for tower crane), (iii) climbing collar support (for tower crane or concrete placing boom), and (iv) installation of a derrick crane with loads applied on the building structure, etc.