Shear & Axial Limit state materials in Series with Fiber

[evgin]

Hi

I use fiber section to simulate flexural behavior in columns in a 3D frame. I also attached axial and shear limit state material including axial and shear limit curve at the top of each column using zero length elements.

Now I would like to record the shear and axial responses in column and plot them against drift!

Should I record the forces (i.e. shear and axial) in the last section (i.e. very end fiber at the column top) of columns? I think the effect of shear and axial springs should be already incorporated into these forces as by assigning zero length elements to the top of the columns, they are gonna be in series with column.


It is interesting since I have numerous springs as I have many columns and I use the following command to assign axial and shear behavior to column

equalDOF $nodeid $slavenode 1 2 3

element zeroLength [expr $level+10000+$count] $nodeid $slavenode -mat $shearTag $axialFailTag $shearTag $centerSlipTag $centerSlipTag $centerSlipTag -dir 1 2 3 4 5 6

but when I am recording the responses in various springs, most of them give me columns of zeros with a few numeric values but some of them give me column of numbers and I was wondering why this is happening ?