Can strain exist without deflection?

  • Thread starter Thread starter wasif
  • Start date Start date
  • Tags Tags
    Deflection Strain
Click For Summary
SUMMARY

The discussion centers on the relationship between strain and deflection in structural elements, specifically addressing whether strain can exist without observable deflection. It is established that any applied stress, regardless of its magnitude, induces some level of strain, although it may be negligible if the stress is below a certain threshold. The definitions of strain as a normalized measure of deformation and deflection as the displacement of a structural element under load are clarified. The conversation emphasizes that strain can occur even in thick walls, contingent upon the constraints present.

PREREQUISITES
  • Understanding of basic mechanics principles, including stress and strain.
  • Familiarity with definitions of deflection and deformation in engineering contexts.
  • Knowledge of structural constraints and their effects on material behavior.
  • Ability to interpret diagrams related to strain and deflection.
NEXT STEPS
  • Research the relationship between stress and strain in materials using Hooke's Law.
  • Explore the concept of surface slips in materials under load.
  • Study the effects of different types of constraints on structural deformation.
  • Learn about advanced topics in material science, such as plastic deformation and yield strength.
USEFUL FOR

Engineers, material scientists, and students studying mechanics who seek to understand the nuances of strain and deflection in structural elements.

wasif
Messages
4
Reaction score
0
Lets take an example of a person pushing a thick wall, of course no deflection in the line of action of force is seen but can strains be induced in it, like surface slips?
 
Engineering news on Phys.org
The definition of strain is dL/L. Stress less than some limit should cause no strain.
 
wasif said:
Lets take an example of a person pushing a thick wall, of course no deflection in the line of action of force is seen but can strains be induced in it, like surface slips?
What are surface slips?

Chet
 
Doug Huffman said:
The definition of strain is dL/L. Stress less than some limit should cause no strain.
This is not correct. Any stress will cause a strain. But, if the stress is very low, the strain might not be significant.

Chet
 
  • Like
Likes   Reactions: Dr.D and billy_joule
via wikiapedia: http://en.wikipedia.org/wiki/Deflection_(engineering), http://en.wikipedia.org/wiki/Deformation_(mechanics),

I believe you can have a displacement at the line of action even in a thick wall. Unless there is some sort of rigid constraint that prevents that.

deflection is the degree to which a structural element is displaced under a load. It may refer to an angle or a distance.

strain is a normalized measure of deformation representing the displacement between particles in the body relative to a reference length.

So, I think it depends on the constraints. Otherwise there will be a strain under any deflection, no matter how small. Check out my picture it may help.
 

Attachments

  • fr84_Picture6.jpg
    fr84_Picture6.jpg
    33.1 KB · Views: 510
strain will be induced due to its own weight also.So,strain will always be present.
 
Chestermiller said:
What are surface slips?

Chet

Hi chet, thanks for the reply

Surface slips by which i mean the deformation of the slip planes at the surface if the force is just enough.
 

Similar threads

Strain Energy Functions and Springs
  • · Replies 2 ·
Replies
2
Views
1K
A500 steel tubing beam deflection
  • · Replies 2 ·
Replies
2
Views
3K
Calculating Membrane Deflection of Clamped Rectangle
  • · Replies 2 ·
Replies
2
Views
2K
Designing an instrument with strain gauges
  • · Replies 6 ·
Replies
6
Views
5K
What causes low pressure on a wing?
  • · Replies 36 ·
2
Replies
36
Views
9K
Need help to verify an attempt to explain strain as point property
  • · Replies 3 ·
Replies
3
Views
2K
High School Strain on a foil sheet separating two compartments in a cylinder
  • · Replies 4 ·
Replies
4
Views
1K
Undergrad Charge movement relative to magnetic field frame dependence/invariance
  • · Replies 5 ·
Replies
5
Views
1K
Calculate the sag (deflection) of a membrane
  • · Replies 7 ·
Replies
7
Views
2K
Deflection of light passing the Sun
  • · Replies 3 ·
Replies
3
Views
1K