Force and initial stiffness of the bolt based on Eurocode 3 part 1.8

Here is a simple sheet and summary of how to determine force and initial stiffness of the bolt based on Eurocode 3 part 1.8.

For determining the force, we only need to know the bolt size/type.
For determining the initial stiffness, there are two important parameters that have direct effect on bolt’s initial stiffness/elongation: Size of the nut and size of the washer.