Simple Question - Preloading of a Cantilever Beam

[CapedCaper]

 

Hello, everyone.

I have been trying to understand the meaning of the question from the posted image.

I think that preloading has to do with adding bolts to the cantilever beam such that it can withstand the force from above, but I am not sure how exactly these bolts should be implemented.

I would also like to generate a meaningful equation based on the information provided.

[studiot]

Looks like homework to me.

What is your course definition of 'Preload' ?

To me, Preload is term used for composite materials such as reinforced concrete to allow a (slender) member to be cast elsewhere and lifted into position without sufferenign damaging transit stresses it would not encounter in service.

But perhaps your course tutors have other ideas.

So please provide more detail.

 

Edit

The other reason I could think of for preloading might apply to a beam that could achieve a permanent set, eg a glulam beam.
Here an upward curvature would be applied to the beam, as near as calculable equal but opposite to the eventual service downward curvature so that it would end up horizontal.
I have used this upward curvature to preset falsework prior to casting concrete beams in place for the same reason, though this was not due to a preloading force but a preset geometry.

Edited January 1, 2019 by studiot