As part of some experimentation on a bolted joint, I have used an instrumented bolt with a number of strain gauges.
The testing has produced results of strain with respect to time. By using the Elastic Modulus of the bolt I can easily convert this into mean stress in the bolt. My question is how this relates to clamping force in the joint.
Is it as simple as averaging this stress over the loading area (i.e. bolt head and nut clamping surfaces) to attain a clamping load?