How much force is needed to bend a fixed beam channel by 4mm at 'F'?

Click For Summary

Discussion Overview

The discussion revolves around calculating the force required to bend a fixed beam channel by 4mm at a specified point, referred to as 'F'. The inquiry includes considerations of the beam's material properties, dimensions, and structural characteristics, particularly focusing on the challenges posed by the channel section and its fixed supports.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant requests assistance in calculating the force needed to bend the beam, highlighting a lack of clarity in the provided sketch regarding dimensions and support conditions.
  • Another participant emphasizes the necessity of knowing the channel's dimensions, the length of the channel, the location of the applied force, and the type of fixity at the ends to provide accurate advice.
  • There is a request for information about the material of the beam, which is crucial for the calculations.
  • A participant specifies that they are looking for formulas to determine both the force causing 4mm of deflection and the force at which plastic deformation occurs, noting that the beam is fully fixed at both ends.
  • Concerns are raised about the structural discontinuity at mid-span due to a notch in the flanges, indicating that standard beam formulas may not apply and that a more complex analysis is required.
  • Another participant suggests that a numerical simulation may be necessary for an accurate calculation, pointing out the importance of the notch dimensions in the analysis.
  • One participant speculates about bending the beam by applying force at the center, but acknowledges this is a gut feeling rather than a calculated approach.

Areas of Agreement / Disagreement

Participants express uncertainty regarding the necessary parameters for calculation and the applicability of standard formulas due to the beam's structural characteristics. There is no consensus on a specific method or formula to use, and multiple viewpoints on the complexity of the problem remain.

Contextual Notes

The discussion highlights limitations in the provided information, such as missing dimensions and material properties, which are essential for accurate calculations. The presence of a structural discontinuity complicates the application of standard beam theory.

mjonquiere
Messages
2
Reaction score
0
HELP! how to calc the force needed to bend this fixed beam channel by 4mm at 'F'http://www.engineersedge.com/engineering-forum/attachment.php?attachmentid=1254&stc=1
 

Attachments

  • CHANNEL BEAM WITH CENTRE LOAD.png
    CHANNEL BEAM WITH CENTRE LOAD.png
    1.9 KB · Views: 630
Physics news on Phys.org
It's not clear from the attached sketch what the dimensions of the channel are, what the length of the channel is, the location of the applied force, or if the channel is fixed at one end only or at both ends. Without additional information, advice can't be given.
 
Also, what the material is.
 
Hi All,
thanks for feed back. I am after a formula to find what force (F) the beam can withstand before plastic deformation and what force (F) caused it to bend by 4 mm.
It's a fully FIXRED beam fixed both ends, the difficulty for me is that its not a normal square beam it's a channel section. attached is a better drawing but its the formulas I'm really after.
 

Attachments

  • Untitled.png
    Untitled.png
    3.7 KB · Views: 587
mjonquiere said:
Hi All,
thanks for feed back. I am after a formula to find what force (F) the beam can withstand before plastic deformation and what force (F) caused it to bend by 4 mm.
It's a fully FIXRED beam fixed both ends, the difficulty for me is that its not a normal square beam it's a channel section. attached is a better drawing but its the formulas I'm really after.
It's worse than that, I'm afraid.

The beam has a structural discontinuity at mid span with that notch in both flanges. You can't apply the regular beam formulas because they are derived assuming that the beam is continuous between supports with constant section properties. You can analyze this beam to determine the deflection and the stress, but it's more than just plugging numbers into a formula.
 
Are you looking for an order of magnitude estimate or something better? I think you need a numerical simulation to calculate it reasonably accurately. It's pretty involved. You are missing the dimensions of the notch in the drawing.

I'm guessing I could bend it by stepping on it in the center with both ends supported, but that's just a gut feeling
 

Similar threads

Undergrad Calculating Combined Loading Stress: Neutral Axis and Bending Moment at Point A
  • · Replies 3 ·
Replies
3
Views
1K
Undergrad Base Motion and Vertical Beam - Basic Reaction Forces?
  • · Replies 9 ·
Replies
9
Views
2K
Undergrad Shear force and bending moments graph
  • · Replies 25 ·
Replies
25
Views
3K
Engineering Cantilever and encastré beams: bending moment and shear force
  • · Replies 2 ·
Replies
2
Views
3K
Bending a beam from straight to an arc with axial force
  • · Replies 7 ·
Replies
7
Views
2K
Cantilevered and line-loaded steel beam
  • · Replies 19 ·
Replies
19
Views
1K
Graduate How weight affects surface bending over time
  • · Replies 10 ·
Replies
10
Views
2K
Graduate Max Bending Moment of Rigidly Clamped Beam
  • · Replies 1 ·
Replies
1
Views
7K
Bending moments about two different axes
  • · Replies 11 ·
Replies
11
Views
3K
Engineering Solving Stresses in Beams: Reactions at B & F
  • · Replies 3 ·
Replies
3
Views
2K