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vesna, Sorry to make a nuisance of this. But if only half the pile area is modelled on the line of symmetry, and earthquake shaking is applied parallel to the line of symmetry. Then earthquake pressures will be converted to loads in the pile based on half the pile area. So if the full pile was model...

I'm sorry to be a nuisance, but could someone please help me out here?

mlw

Hi all, I have a question about bending moments as given by the globalForce recorder. I am modelling a circular pile surrounded by soil on the line of symmetry (i.e. the finite element mesh consists of only half the model). The bending moments that I am getting during dynamic loading are roughly hal...

I will look into it.
Thank you for your help.

Yes, all my pile nodes are fixed in the 2nd, 4th, and 6th DOF.

vesna, Thank you for your time in answering my question. The globalForce recorder is: eval "recorder Element -file pileReaction.out -time -ele $pileEleList globalForce", where pileEleList is the list of pile elasticBeamColumn elements. This is the command to create the pile elements. Element 1525 is...

Hi all, I have been modelling a pile that is rotationally free at the both the tip (burried in the ground) and the head (at or slightly above ground level). There is nothing to restrain these ends against bending, so the moments at these points should be zero. But when I look at the output from my g...

vesna,

Yes I have applied a scaling factor in the path timeSeries. I suspect the problem could be due to wrong equalDOF constraints on the nodes at the base of the model where the earthquake is being applied. Will get back to you if this doesn't solve the problem.
Regards,

mlw

vesna, I figured out why it wasn't working. The nodes that I am applying the loads to were created in 4dof, and I was adding the load in 6dof. The load should have been added in 4dof. The problem that I am getting now is that the load is not being added!!! The model runs smoothly (suspiciously smoot...

vesna, I have checked the model for errors. But I don't think there is a mistake in the rest of the code because it runs fine when I use a uniformExcitation pattern to apply the EQ load. What would cause an "addunbalLoad" error? Could it be that these commands were made for 3dof or 4dof models, not ...

Hi all, I am trying to model an earthquake, and need to apply the earthquake loads to the base of the model only. What I have done in the past was to use the uniform excitation command, but I understand that this applies the excitation to all node in the model not the base of the model only. So what...

Hi all, I have been using the p-y spring method in OpenSees Laboratory to verify my numerical model. One of the user inputs in the OpenSees laboratory model is the shear modulus of the soil, but it doesn't say what confining pressure the shear modulus should be specified at. Could anyone tell me wha...

That makes it a lot clearer now.
Thank you for your help.

- mlw

Hi vesna, The relevant commands follow for my most recent version of the code (the load is different amongst other things): #pushover loading applied to the top of the pile at ground level pattern Plain 2 Linear { load 2115 0 0 -500 0 0 0 } #create parameters for fourth analysis set alpha 0.100000 s...

Hi all, I have linear timeSeries with no load factor (i.e. a load factor of 1). Then I apply a load of 300kN to the top of my pile in the z direction. The analysis runs at 0.1sec time intervals. When I check the load that was applied (shear in the z direction as given by globalForce), I see that it ...