×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Difference between Section Force SF and NFORCSO in beam

Difference between Section Force SF and NFORCSO in beam

Difference between Section Force SF and NFORCSO in beam

(OP)
Just a quick question.

When using a beam element, is there a difference between Section Force SF1 and NFORCSO1?
Both give axial forces within the beam.

The same question applies to the other components:
SF1 = NFORCSO1 Axial
SF2 = NFORCSO2 Shear
SF3 = NFORCSO3 Shear
SM1 = NFORCSO4 Bending
SM2 = NFORCSO5 Bending
SM3 = NFORCSO6 Torsion

I have checked with a simple beam under tension, shear force bending and torsion an these relations are confirmed.

I found this section in the Abaqus verification guide:
5.2.5 Element nodal forces in beam section orientation

Quote (Abaqus Verification Guide)

Features tested

Output variable NFORCSO gives the element nodal forces caused by stress in the element in the same coordinate system used to output section forces and moments. NFORCSO differs from NFORC only in the coordinate system used for output: NFORCSO components are the internal forces in the beam coordinate system, while NFORC components are internal forces in the global coordinate system.
Problem description

An L-shaped cantilever beam has concentrated loads applied at its free end. The length of each segment is 10 in., and the beam has a square cross-section with 0.10 in. sides. Steel elastic material properties are used (Young's modulus of 30 × 106 psi and Poisson's ratio of 0.3). Since the beam is slender, we choose to have the slenderness correction coefficient (SCF) computed from the elastic material definition; by adding the label SCF in the transverse shear stiffness definition, we obtain improved results with the linear Timoshenko beam elements B21 and B31.
Results and discussion

The results illustrate how the variable NFORCSO provides a more convenient way of examining results along beams, especially the case in long linear Timoshenko beam elements, since these elements possess a single integration point along the length of the beam. Output variable NFORCSO provides the bending moments at the extremities of the element, thus depicting the linearly varying bending moment distributions in the problem at hand. In quadratic Timoshenko beam elements B22 and B32 all NFORCSO components vanish at the center nodes as expected.

In this tutorial the instructor is using NFORCSO2 and NFORCSO6 to plot Shear and Bending Moment diagrams (2D beam): https://www.youtube.com/watch?v=nk6iX4eFJZE
The same could be done with SF and SM or not?

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources