Can anyone tell me the difference between RESTRAINED & CONSTRAINED?3Q
Can anyone tell me the difference between RESTRAINED & CONSTRAINED?3Q
(OP)
Can anyone tell me the difference between RESTRAINED & CONSTRAINED?3Q
I find it is difficulty to understand ,
will u give me some eg?
I find it is difficulty to understand ,
will u give me some eg?
RE: Can anyone tell me the difference between RESTRAINED & CONSTRAINED?3Q
Constrained: you "tell" to a joint to have the same movement of another joint (or more than one), this may be the same displacement, the same rotation .... etc
RE: Can anyone tell me the difference between RESTRAINED & CONSTRAINED?3Q
Restrained:Can i set the top point in the frame Restrained?
vincolated ?what does it means?I look up in the dictionary,and find none.Does it means the point connect with the ground?
RE: Can anyone tell me the difference between RESTRAINED & CONSTRAINED?3Q
Vincolated does not exist, but does vinculated exist or not?
RE: Can anyone tell me the difference between RESTRAINED & CONSTRAINED?3Q
Joint constraints are different from restraints. Constraints are used to connect 2 or more joints together in any or all degrees of freedom, including the effects of the offset distance between the joints. Select joints, then Assign menu>Joint>constraints
RE: Can anyone tell me the difference between RESTRAINED & CONSTRAINED?3Q
I had difficulty with joint constraints, when I constrained a number of joints together. What happened is, static equilibrium was not satisfied for the model. The lateral loads times the moment arm about the base (a point) did not equal the reaction loads about the same base (a point). This is pretty easy to check, by putting a single load on the structure.
So, if I use joint constraints, I will check that these constraints have not extracted some moment out of the problem, and this could be substantial. What I ended up doing is using rather stiff spring connectors between joints rather than joint constraints between joints.
RE: Can anyone tell me the difference between RESTRAINED & CONSTRAINED?3Q
I wonder if maybe the self weight or some other loads got included in your reactions and that threw you off?
Maybe I misunderstood, but I don't see how SAP's constraints 'extract out the moment' in a model. Maybe you can provide more details. And when you say you used 'spring connectors', are you referring to a 2 point link?
RE: Can anyone tell me the difference between RESTRAINED & CONSTRAINED?3Q
I also tried the model you suggested.
>>one joint 10 ft above the other and assign a body constraint to both joints for all 6 dof. Assign restraint on the bottom joint in 6 dof. Assign a lateral load to the top joint of, say 1 kip. Restraint reaction is 10 kip-ft moment as expected<<
But it doesn't work. The error message says "more than one constraint, restraint and/or substructure external connection applied at DOF ... at joint ...". Even if I apply only one restraint (rotation about 2) it doesn't work. Any thoughts?
RE: Can anyone tell me the difference between RESTRAINED & CONSTRAINED?3Q
RE: Can anyone tell me the difference between RESTRAINED & CONSTRAINED?3Q
My point was that use of constraints do satisfy static equilibrium in every case that I've seen and considers offset distance between constrained joints. I am still confused by jrmack's comment about SAP2000 constraints 'extracting out the moment'.