Questions tagged [buckling]
The buckling tag has no usage guidance.
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Hollow circular columns vs solid circular columns of exactly the same mass and length, which resist buckling better?
I've seen a number of mentions in the tensegrity literature asserting (without proof or reference) that, in the context of a tensegrity rod under pure axial compression, hollow columns perform better ...
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Stress concentrations around rivets in compression
The stress concetration factor for an unfilled hole is around 3, but it decreases when a rivet is present. What factor can we expect for a hole with a rivet in it in compression?
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Buckling length of continuous steel H columns in multi story buildings
I have seen that steel columns in multiple story buildings span multiple stories, in that case how do you calculate the buckling length for the column? do you take the whole column's height, or just ...
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Calculation of critical column buckling load using Johnson's formula, but with eccentricity?
I've got partial answers but nothing comprehensive found online - most online resources focus on Euler's buckling formula which isn't appropriate for shorter columns.
Data I have collected:
Column is ...
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Eccentricity for staggered 2x4 wall
I have a staggered 2x4 wall on a 2x6 sill plate as illustrated below (16" on center on each side = 8" on center each stud). The wall is loaded from both sides by floor joists, so I would ...
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Minimal width of a carbon fiber shell to hold a flying airship
In Aves Æternæ: Building Perpetual Flying Machines you can find the specs for an airship with a rigid carbon fiber shell. It would be around 4m long and 2m wide and high, weigh around 10 kg empty (0 ...
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Determining the critical load of a fixed beam with non-uniform cross-section?
I am a computer scientist, not a mechanical engineer, so it is absolutely possible that I am missing some basic understanding here.
I have a beam that is fixed in both ends and my goal is to ...
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Meaning of this sentence in lecture notes about buckling of nonlinear column
Above picture is from my lecture notes. It deals with a column subject to axial load, which follows Euler buckling theory. The material is nonlinear, approximated by two lines as seen in the stress-...
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MSC Nastran - BAR3/4 elements - can't assign any properties
I'm modeling a pipe in Patran, and I'd like to try bar3 and bar4 elements.
I assing the properties CBEAM to my geometry, but when I create the mesh, Patran tell me bar3 and bar4 don't support that ...
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Interaction of buckling modes
I'm reading this paper on structural members subject to both bending and compression.
In the first paragraph, in context of the equations 6.61 and 6.62, it is said:
The second two terms are modified ...
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Is there a way to program a buckling analysis of an arbitrary shape, using a standard programming language/libraries (not Abaqus)?
I am trying to develop a program in Python that runs a few different basic analyses for optimization like minimizing compliance and buckling. I want to use machine learning to try to develop a fast (...
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Can a buckling steel column fracture on multiple points?
When a column buckles, then yields, and finally fractures fractures, along the most stressed point, this will initially reduce the axial and bending strains along other points. The apparent conclusion ...
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How to calculate maximum buckling load for hydrofoil strut?
I am a hobbyist and in the process of designing a human-powered hydrofoil (see Hydroped for reference) I'm kind of stuck in the calculation of the the maximum buckling load for a strut.
The strut is ...
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Describing 180 degree arcing/deflection of wire supported vertically at one end
I am trying to understand how to describe and calculate the shape a length of piano wire makes from its own weight when supported vertically at only one end. Is it a catenary or a parabola? ...
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What is the critical buckling force needed to be applied on a system of made out of two parts?
What is the critical buckling force needed to be applied on a system of made out of two parts?
The parts of the system are as depicted in the picture:
incompressible elastic beam - on top
...
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How to compute core stress in honeycomb structure?
Assume I have a honecomb(sandwich) panel under distributed normal load. Each edge of this panel is simply supported(pinned) as on the picture below:
The problem is how to find the core stresses σ-z (...
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Why isn't lateral torsional buckling of rectangular timber members dependent on torsional stiffness?
I'm reading about buckling of timber members from Eurocode 5: Design of timber structures part 1.
Section 6.3.3 gives instructions to check the stability of beams subject to compression, bending or ...
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How to find the tension in wires before a column buckles
I already have the solution for this problem, I just need some explanation about a certain part. Can someone please explain the highlighted section, how do I obtain the tension formula used here?
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Stability of solid rectangular wood member
I'm reading about buckling of timber members from Eurocode 5: Design of timber structures part 1.
Formula 6.30 gives the relative slenderness of a member:
$$\lambda_{rel.m} = \sqrt{\frac{f_{m,k}}{\...
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Do yielded columns buckle?
A sufficiently slender column will fail under compression below yield stress by bowing, releasing it's axial elastic strain. This is called buckling. Depending on the slenderness of the column, the ...
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Shear capacity according to eurocode , when to use which equation
I am looking at eurocode to calculate shear capacity, and under section "6.2.6 Shear", there are two different shear checks:
Eq 6.18
Eq 6.19
When there is no torsion we can use equation 6....
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Why is buckling said to be independent of material strength?
In many sources, such as here, it is said that buckling failure is independent of the material's strength.
But in many building codes, yield stress of the material is a factor that changes the ...
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Why does figure 2 and 6 deform differently from the other shapes?
I am doing a linear buckling analysis on all the structures you see below, they are subjected to compression load in the x-axis as indicated by the arrow. You can see all structures beside 2 and 6 ...
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How do I find the buckling strength?
I am running something called cell periodicity study in comsol, which finds the material properties of a model. It is done by applying a uniaxial compression load, and performing a nonlinear buckling ...
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Do these linear vs nonlinear buckling plots make sense?
I am doing linear buckling analyses (where everything is linear), and nonlinear buckling analyses where you have nonlinear geometry enabled and nonlinear material behavior (hyperelastic material). ...
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Why do we need to have perturbation in our system to do buckling analysis? [closed]
Do we need it for both linear and nonlinear system?
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(Follow up) Can a thicker model giver a lower critical buckling load?
I present three seperate models with thickness of t = 0.005m, 0.01m and 0.025m respectively, all have a forced displacement of -0.01m in the x-direction, and fixed on the other end. As you can see the ...
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Can a thicker model have a lower critical buckling load?
I perform a linear buckling analysis for two similar geometries, where one model has thickness t = 0.01 m, and the other has thickness t = 0.035 m. Otherwise everything is exactly the same. The ...
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How is a linear buckling test supposed to look like?
If I had a cube like object; would this be a good way to set up a linear buckling analysis?
https://i.stack.imgur.com/Wqphm.jpg
And no other forces or boundary conditions
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Solver cannot find any eigenvalues for linear buckling analysis [COMSOL]
I am trying to do a simple linear buckling analysis, where one end is fixed and the opposing end has a prescribed displacement of -0.1m in the x-direction that compresses the structure. Solver cant ...
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What Causes Asymmetrical Buckling in this structure?
I've been playing around with structural modelling on the SkyCiv platform and have created this structure, related to a project I am working on to educate myself.
It is 2m wide, 3m long and 1.5m high ...
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Why does the upper wing skin fail in buckling and lower wing skin does not?
I am aware of the fact that the buckling is mainly caused in the regions of the specimen which are in compression. But the wing skin doesn't take any axial loads and is used to resist shear, atleast ...
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Twist "buckling" critical load
I have a very long beam which is subjected to a torque (I have the moments and shear forces with respect to X along the beam). I can calculate the critical load when the beam would bend if it was ...
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How to calculate how much compression is needed for a spring to buckle
First off; School was many years ago and I know little of the mathematics behind all the physics and engineering stuff. So if you have an answer, please explain it like I'm 5?
The goal: I aim to be ...
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Program name of this buckling modeling
My instructor sent this solving with program that I don’t know the name , does anyone know the name of the program ?
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maximum allowed load [closed]
I have the following problem
E= 210 MPa
d = 40 mm
n = 20
y = 1.5
a =1
calculate the maximum allowed load for the system
I am confused on how to solve the problem, I really need advice.
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unbraced length of the compression portion of a long member
I am designing a truss. the bottom chord in the first two panels at each end or at the supports are in compression and the rest of the bottom chord is in tension. there is no lateral bracing along the ...
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ABAQUS: How to connect a shell edge with a shell face?
I'm performing a buckling analysis of a stiffened aluminium panel. The panel and flatbar stiffener(2) is created as one 3D shell extrusion. The T-stiffener (1) is another 3D shell extrusion.
How do I ...
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Buckling of Parallel rods
I am trying to calculate critical force $P$, if two rods (same diameter and length - rigid fiberglass sandwiched on two steel plates) are parallel to each other.
$$
P = \frac{\pi^2 EI}{(KL)^2}
$$
I ...
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How do I calculate how many newtons a hollow rod can carry without buckling?
how can I calculate how many newtons a 600[mm] long rod with a known yield strength (300 [MPa]), young modulus (190 [GPa]) and hollow (outer diameter = 16[mm], inner diameter = 10[mm]) will carry ...
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Beam buckling criterion?
If I have an I beam which I subject to some bending load, how can I calculate when the thinner middle part of the I beam will buckle? I though I could use Euler's critical load formula here, but it's ...
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How do FE solvers solve the case of panel buckling under pure shear?
How do FE solvers solve the case of panel buckling under pure shear?
The main problem is that global matrix of initial stess is singular in that case. One method is to apply some forces that shear is ...
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Using modes from linear buckling analysis as imperfections
I'm reading this article on buckling.
It first introduces us to linear buckling analysis, and then mentions that linear analysis can be unrealistic as it doesn't take imperfections into account. Then ...
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Why is local yielding considered the limiting case in context of buckling in Eurocode?
In Eurocode, when use buckling curves to calculate the maximum load that a compressive member can be subjected to before it risks buckling. Buckling curves are based on the Perry-Robertson formula. I'...
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Definition of buckling as a sudden deformation
On Wikipedia, buckling is defined as follows:
In engineering, buckling is the sudden change in shape of a structural component under load such as the bowing of a column under compression or the ...
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Can the critical buckling load from non-linear FE calculation be higher than the one from linear?
Let's consider a FE buckling calculation without plasticity.
Is there theoretically any chance that the non-linear analysis will give a higher buckling load than the linear one?
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For arc-length method in nastran, how to analyse post-buckling behaviour with load decrease
I am currently trying to model the buckling behaviour of a cylinder using sol 400 nonlinear static analysis using Nastran. I am using the arc-length (modified Riks) method as apparently it can ...
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How would I do a buckling analysis with an additional fixed known lateral force?
I am using Nastran for buckling analysis, and I'm new to all of this so please bear with me.
For a linear buckling analysis, I understand that you must first apply any compressive load in the static ...
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Why is buckling caused by nonlinear geometry?
I've been reading the Comsol post on geometric nonlinearity. The article introduces situations where the small angle approximation and linear analysis of structures gives inaccurate results. For ...
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What is meant by "perfect geometry" in the context of Euler buckling?
In this question for example (in the first answer) it is said that the Euler critical load formula is unrealistic, because it assumes perfect geometry and perfect alignment of the load. I've found ...
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