Simple Clamping Force / friction question 1

[R3345]

In the picture attached, can somebody please explain if the axial force in each side of the U bolt creates 6000 N on each side of the bar , or is the 6000 N divided between each side?

 

[BrianE22]

Whenever there is more than one path for the load to go you have to look at relative stiffness to determine how much of the load goes along each path. In this case the load path from block to plate is very stiff. The path going through the u-bolt, however, includes a transverse load on a near cantilever section of the u-bolt. The cantilever section is not stiff in bending compared to the stiff solid block so little of the load would pass through it.

One approach to equalizing the 2 load paths would be to apply the external load to the middle of the cantilever section of the u-bolt. That may, of course, not be practical in your application. Another approach would be to make the block load path more compliant or the cantilever load path more stiff (in bending I'd think but maybe also in shear).

 

[Denial]

With the diagram the OP provided on 03Oct14@07:29 I suspect the situation transcends analysis.[ ] Depending upon the bending stiffness of the u-bolt, the bar will probably begin to move before the plate does.[ ] Depending upon the amount of relative movement, the bolt will be put into additional tension.[ ] Friction forces increase.[ ] By an unknowable amount.

Impossible to model mathematically.[ ] Probably also impossible to get reliably reproducible results in a physical experiment.[ ] Murphy's Law will prevail:[ ] if you want to induce "binding", it won't happen;[ ] if you want to avoid binding, it will happen.