Calculating constraint reactions

AI Thread Summary
Calculating constraint reactions for the six pads requires understanding the system's hyperstatic nature and the distribution of forces. A FEM analysis using Ansys Workbench can provide valuable data for this calculation. To simplify, one can find the centroid of the pads and treat them as a single reaction pad, with the total vertical force and moment distributed among them. Each pad will then experience a reaction force that is a fraction of the total force and moment, calculated based on their distances from the centroid. This approach helps in achieving equilibrium in the system.
Andrea Vironda
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Constraint reactions on a 6 pads system
I would be interested in calculating the constraint reactions on the 6 pads in yellow in the figure, about 300mm apart among them and loaded with F=12500 kN in blue. Since the system is highly hyperstatic, I don't know how to calculate the constraints. Can you give me a hand?

I've made a FEM calculation using Ansys Workbench v18. Do you think it's possible to read those data from there?
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https://en.wikipedia.org/wiki/Statically_indeterminate#Mathematics said:
To solve statically indeterminate systems (determine the various moment and force reactions within it), one considers the material properties and compatibility in deformations.

But if one wants to assume that the forces are well distributed between the different constraints, one can lump the constraints together.

First, find the centroid of the six pads by averaging Xs and Ys to simulate a single reaction pad. The vertical reaction force on that pad will be ##F## and there will be a moment ##M## created to be in equilibrium.

Then draw a line from that pad to each pad. These are your lever arms and the reaction force to the moment for each pad will be perpendicular to these lever arms of length ##R_n## (where ##n## varies from ##1## to ##6##).

Now assume the vertical force and the moment reactions are distributed equally to each pad, thus each pad will have a reaction force that will be a vector composed of ##F/6## and ##M/6/R_n##.
 
Thanks, it helped me a lot
 
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