Distribution of stress over two points from moment/torque.

[Nougatti]

I'm calculating stresses in bolts and surrounding concrete for this "foot" that supports a column much taller than what I've drawn here:

I know the distances between A, B and C and I know the moment/torque (not so sure on the English here) about point A is 155 kNm.
The question is: in which manner and to what degree do B and C take up this moment/torque? Obviously, because of the triangular "corner-plate", the base plate would act as completely stiff, right?
Also, I know it's can't be a matter of "B and C share the load equally", right? How do I calculate what stresses the B- and C-bolts will be subjected to?

So, what is reasonable here? Is this an impossible task or something one isn't supposed to analytically figure out, but instead just model in ANSYS?

Best regards
Daniel

I am Norwegian.
I design mechanicals for hydroelectric powerplants.
I use NX 6.0.5.3
----------------------------
Tom you can't knit at these speeds! Nobody can! DON'T BE A GODDAMNED HERO TOM!

 

[hokie66]

Nothing is completely rigid, but the force at the bolt lines at B and C can be assumed to be proportional to their distance from A.

 

[Nougatti]

To be conservative, I guess I should calculate with C taking up EVERYTHING, and B just being there "just in case".

I am Norwegian.
I design mechanicals for hydroelectric powerplants.
I use NX 6.0.5.3
----------------------------
Tom you can't knit at these speeds! Nobody can! DON'T BE A GODDAMNED HERO TOM!

 

[rb1957]

is it reasonable that the base (a plane) remains planar ? if so, a linear distribution would serve.

i think the most conservative path is to consider various loadpaths ...

1) react the moment between B and A (using A as the compression loadpath is conservative and simplifying (the "real" reaction is a triangular distribution from B to the edge)

2) react the moment between C and B (this is clearly conservative)

3) react the moment between C and A (clearly not critical compared to above)

Quando Omni Flunkus Moritati

 

[Cockroach]

I would convert the torque to a force acting at a distance from point A, the tipping point. You know that this force would a t throu the centroid of the rectangular looking tower. You say you know the bolting pattern.

Sum the forces in the vertical direction, then sum the moments about point A given the bolts retard the action of this moment. You have two equations in two unknowns, which permits a closed form solution.

But a nice homework problem, first year statics?

Regards,
Cockroach

 

[desertfox]

Try this link

thread507-337949

Go to the attachment I posted for the above thread it should help

 

[zekeman]

I would also assume a triangular distribution for the bracket and then the resultant force would be 1/3 the distance between B and C.
Call this F. The other force F would be located at the center of the foot.
These 2 forces form the couple,FL that equals M
Now you have 6 bolts sustaining the two F forces. making it indeterminate.
However, one more assumption -- A looks like pivot point, allowing the forces in the C bolts to be twice the force as the A bolts.
satisfying moment equilibrium abot A would yield B and C forces.
This is not a recommended solution but only one approach to a possible solution.You could entertain other scenarios and come up with reasonable answers.
Probably the OP may have the best conservative approach, namely putting all the load on the C bolts and use a hefty FOS.