Frame with mutipoint constraint? 1

• Oct 23, 2002

• #2

EdR

Structural

Oct 11, 2002

191

US

Define your MPC so that the proper global DOF times the sine and cosine of the angles gives a normal displacement component of zero.

 

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• Oct 23, 2002

1
• #3

pjhype

Mechanical

Sep 11, 2002

78

US

Or, you could define a local coordinate system at the roller support inclined at 30 degrees and constrain only the motion in the normal direction.

 

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• Oct 23, 2002

• Thread starter
• #4

idly123

Structural

Jun 12, 2002

96

IN

Wouldnt the cosine term(horizzontal) calculated from Dof at roller affect the behaviour of he roller in that the horizontal movement at roller would be affected??!

If that is the case can an inclined roller be equivalent to a hinge with a force acting equivalent to the cosin component......can such an argument be valid
please let me know
regds Raj

 

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• Oct 24, 2002

• #5

EdR

Structural

Oct 11, 2002

191

US

1. If constraint of local coordinate systems is available then pjhype's suggestion is the same as mine and probably easier to accomplish...

2. I didn't really understand your question but maybe this will help...both the horizontal and vertical (assuming these are global dof) deflections will be affected by such a constraint. They will be affected in such a way that their final values will give a zero deflection normal to the inclined slope...Unles otherwise constrained the deflection parallel to the slope will be non-zero..

Ed.R.

 

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