The stress-strain tag has no wiki summary.
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Decomposition of deformation into bend, stretch and twist?
I'm wondering is there any way to decompose the deformation of an object into different components? For example, into stretching, bending and twisting part respectively? The decomposition could be ...
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0answers
21 views
The stress in copper and steel parallel compound members [closed]
Came across this question and just needed abit of help undertanding how i should go about this question
I have also attempted to solve it to the best of my ability but im stuck.
A concrete column of ...
1
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1answer
84 views
Why can we analyse force balance on a dislocation?
Dislocation (like screw or edge dislocation) is not a 'real' thing, while Newton's laws only apply to a real object (no matter macroscopic, like stars, or microscopic, like atoms).
In the derivation ...
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2answers
137 views
Standing Waves Energy transfer
And In a standing wave , how does energy travel past a node in a string ?
It should just get reflected . Assume the case of first overtone and you strike the string at a place . How will energy ...
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0answers
23 views
What diameter is used to calculate stress in an elastomer whose cross sectional area changes continuously when streched?
Consider a cylindrical rope of rubbery elastomer with a radius (in inches) equal to the square root of the inverse of $\pi \rightarrow \sqrt \frac{1}{\pi} $ so that the cross sectional area is $1 \, ...
2
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1answer
142 views
What happens when a piezo crystal is exposed to a vacuum?
Application of mechanical stress to a piezo crystal generates a charge.
Quoting from wikipedia, a 1 cm3 cube of quartz with 2 kN (500 lbf) of correctly applied force can produce a voltage of 12500 ...
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1answer
76 views
It would take an elephant, balanced on a pencil, to break through a sheet of graphene the thickness of Cling Film
I'm currently doing some work on a presentation about graphene, and have come across numerous articles which claim something along the lines of
It would take an elephant, balanced on a pencil, to ...
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1answer
53 views
Hollow stone columns provide more support?
In history class in elementary school I remember learning that the Greeks would build their stone columns hollow because they thought this provided more support. Is it true that a hollow column is ...
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0answers
73 views
I have some problems doing simple stress analysis on a beam being bend
In a assignment I have this beam that is under a bending load. Failure can occur due to shear or normal stresses. My task is to determine the location where the maximum stress occurs as a function of ...
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4answers
311 views
What is a strain gauge and how do I use one?
As the title says, I have no idea what these things are or how to get or use one. Can I receive a simple explanation or links to one? I'm a computer engineer so I have very little physics/mechanical ...
2
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1answer
66 views
Why is $dL = L d\epsilon$?
Let's say there's a random elastic material. It's length is $L$ and it's tensile strain $\epsilon= (L-L_0)/L_0$
Now, when one pulls on it the following is true:
$dW_{tot}=FdL =\sigma AdL=\sigma A L ...
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0answers
27 views
How do I minimize the the stress created by fore-aft forces?
My friends and I are designing a bench press spotter. Essentially, when the user needs help lifting the barbell due to muscle fatigue, an arm on each side of the user raises to provide assistance. ...
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0answers
77 views
Whats the contact area for elastic contact between a cylinder and a plane surface?
I am trying to determine the contact area between a cylinder and a plane surface of two different materials so that the plane lies tangent to the cylinder. There is elastic contact between the two ...
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3answers
119 views
Glass pipe cutting
I want to know how to quickly create the straightest possible breaks in glass pipes
I apologise if this is only borderline suitable for a physics forum - I just hope experts with a lot of experience ...
3
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1answer
117 views
Material strain from spacetime curvature
Let's say that you moved an object made of rigid materials into a place with extreme tidal forces. Materials have a modulus of elasticity and a yield strength. Does the corresponding 3D geometric ...
3
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2answers
106 views
Does zero strain always imply zero stress?
In solid mechanics, can I always assume that if an object undergoes no strain, then no stress is applied to it? I think it's true only because I can't seem to find a counter-example.
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51 views
Continuum mechanics and effects of stress
Going to word this question a bit more straightforward than I may have before. Also, I'm trying to use baby formulas so I can grasp exactly what's going on.
Object A has an elasticity of ...
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1answer
71 views
Is shear elasticity the same as shear modulus?
I've encountered both the terms "shear elasticity" and "shear modulus". Are these the same?
3
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1answer
201 views
Why does glass break at the line where you score it?
Why does it take such a small incision for the glass to break at that spot? Why is the structural strength of the material influenced by such a small imperfection?
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1answer
98 views
How wide does a wall of ice need to be to stay in place?
Let us say that we have unlimited manpower to construct a huge wall of water ice e.g. 200 m tall (700 feet). -and that the wall is placed in a climate, where the temperature never (for your purpose) ...
2
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1answer
160 views
What is the two dimensional equivalent of a spring?
I'm trying to model isotropic linear elastic deformation in two dimensions. In one dimension, I know that a linear elastic material can be thought of as a spring which obeys Hooke's law $F=-k\Delta ...
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0answers
165 views
Free body diagram of stresses governing fracture propagation in a solid material
Reading this, I can intuitively understand that fractures propagate along the path of least resistance, creating "width in a direction that requires the least force". However, it is less intuitive ...
3
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1answer
407 views
Formulas for compressibility of solids
I am taking a course in mechanics this semester, as well as a course in reservoir physics. Both courses have sections devoted to pressure/compressibility of solids, but the formulas look slightly ...
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111 views
free stress analysis software for verifying speaker stand design
I've designed a speaker stand, that I would like to build myself. However, I am a little unsure if the design is sturdy enough, or if it needs further improvements.
Is there a free software, which I ...
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101 views
How to describe halfspace reaction to uniformly distributed load having reaction to a point load of same force? [closed]
Having a functional description of halfspace reaction to a force directed in to the point how to describe its reaction to the Uniformly Distributed Load ( directed in different shapes and forms: rays, ...
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2answers
6k views
Hollow Tube Stronger than Solid bar of same Outside Diameter (O.D.)?
I was listening to some co-workers talking about problems meeting stiffness requirements. Someone said that even with a solid metal rod (instead of the existing tube) we could not meet stiffness ...
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1answer
189 views
Euler's buckling formula applicable for impact calculations?
$$F = \frac{\pi^2 EI}{(KL)^2}$$
Is Euler's buckling formula applicable for impact calculations, considering speeds relevant for a car or aircraft crash?
If there is a level where the formula ...
2
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1answer
199 views
Poisson effect formula for large deformations
English Wikipedia in the Poisson's ratio article gives an equation for large deformation:
$$
\frac{\Delta d}{d}=-1+\frac{1}{\left(1+\dfrac{\Delta L}{L}\right)^\nu}
$$
I couldn't find any reference ...
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2answers
362 views
What is the mathematical formulation for buckling?
Argument: Buckling is an engineering concept that can only be applied to thin columns with compressive loading.
(Is it possible to) Prove the above sentence right or wrong with mathematical ...
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0answers
88 views
Is there analysis library for stress-strain data?
I have three column data that has time-displacement-force from 1D tensile/compression test. Now I would like to get the standard mechanical properties of the material, like Young modulus, yield ...
4
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1answer
528 views
Physical meaning of elastic constants of a monoclinic crystal
For the elasticity of a material, Hook's law can be written in tensorial form as:
$$\sigma = \mathsf{C}\, \varepsilon$$
where $\sigma$ is the Cauchy stress tensor, $\varepsilon$ is the infinitesimal ...
2
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1answer
168 views
Is there symmetry in 2d stress tensor in linear elastic fracture mechanics?
Assumptions:
Cross terms in strain tensor are defined as equal $\varepsilon_{xy} = \varepsilon_{yx}$.
pure mode I crack.
Far from crack tip, material is purely elastic and we are way below
yield ...
2
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1answer
495 views
What is the shear stress of a fluid?
One book defines the shear stress $\tau$ of a (Newtonian) fluid as
$$\tau = \eta \frac{\partial v}{\partial r} $$
where $\eta$ is the viscosity. There is not much context, so I've made some guesses. ...
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3answers
281 views
Calculating stress without strain
I am working on an algorithm for a real-time simulation.
I would like to calculate to extremely permissive tolerances approximate values for the stress within a 2D geometry. It will not be difficult ...
3
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0answers
142 views
Does a thermally expanding torus experience internal stress?
I'm trying to learn continuum mechanics and thermo-mechanics.
As we know, heating an object increases the mean atomic distance $a_0$ of the atoms in a rigid body. Let's assume it is a linear elastic ...
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0answers
52 views
stress work of uniformly deforming continuum
I have a volume which is deforming (using explicit time-integration scheme) uniformly with velocity gradient $L$ and stress tensor $\sigma$. I would like to determine work done by the volume ...
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0answers
701 views
What is the cause of strain hardening and strain softening?
Why is it, that - if displayed in a strain/stress-diagram - the curve will at first be linear, and then change into a "curved shape", where it will first decrease again, and only later increase again? ...
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1answer
216 views
Stresses put through joints on a steel climbing wall
Being a fan of stackoverflow, I thought I could try this question here, hope its not too off topic.
I'm wanting to build a free standing climbing wall in my garden and dont know where to start ...
2
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2answers
259 views
What is the shape of a clamped bent bar?
How would I figure out the Cartesian graph that describes a bar clamped flat for a length on one end with downward force being applied to the other?
I have an idea that the bar will try to average ...
