positive and negative stresses

[Gabriele.Neri]

Dear STKO team,
I have some problems concerning the stresses: in the post processing of STKO I obtain positive and negative values (FOTO 2) as it should be, whereas in the tcl file I obtain just negative values ( The red column in FOTO 3).. I can't understand why. Can you help me?

thanks in advance

[kesavapraba]

Hi, The TCL file lists individual stress components for a specific fiber, while STKO shows a range for all fibers. To confirm, record the same stress component for each fiber and compare the results.

[Gabriele.Neri]

The same thing applies to the bending Moment (M), Shear (V) and Axial sforce (N)?

Thanks in advance!

[STKO Team]

Probably your text recorder in plain tcl is just monitoring the bottom fiber

[Gabriele.Neri]

dear STKO team,

I'm performing a gravity analysis on a double-interlocking beam subjected to uniformly distributed load, but I have some difficulties with the results obtained.
In order to catch the actions in the output I used the recorder element command, as shown in "photo_0".
In "photo_1" the shear diagram plot is shown, in which we can see that shear is positive at one end of the element and negative on the other end (look at the values ​​highlighted in yellow).
In "photo_2" the output of the internal actions is shown: Here we can see that the shear value are always positive (look at the values ​​highlighted in yellow).. I can't understand this change of sign from STKO-Post processing and file in .txt format, can you help me??

I uploaded as zip files the .mpco and the .scd files, in this way you can open it if it can help.

Thanks in advance!!

[STKO Team]

In OpenSees "force" (global) and "localForce" (local) are the opposite of the internal forces at the element nodes (the opposite of the blue arrows in the picture)

In this picture you can see a truss subject to a positive tensile load N, so you would expect axial force constant and equal to N (tension)
But if you record "force" or "localForce", in opensees they are the opposite of the blue arrows, so in STKO we change the sign of those results at the second node when doing the beam-diagram plot

intforce.png (13.19 KiB) Viewed 2538 times