Questions tagged [deflection]
The deflection tag has no usage guidance.
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Rigid frame deflection and material selection
I'm building a frame that will receive a point load mid span (likely it won't be but want to design for worse case).
The frame is 1.5 x 0.095 square tubing, and it will be skinned with 14ga on one ...
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Maximum deflection of PSL + steel beam
I'm an amateur structural engineer, and I'm not understanding how to calculate multi-material beam deflection in my particular scenario.
I start with a simply supported PSL (wood) beam that is ...
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Which Deflection Formula is Correct for Hollow Aluminum Tube, Simply Supported, Uniformly Distributed Load?
Which deflection formula is correct for simply supported hollow aluminum tube with a uniformly distributed load (I've read conflicting answers online):
δ = (5 x w x L^3) / (384 x E x I)
δ = (5 x w x ...
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Searching for geometric modeller to investigate behaviour of beam when deflected
I have the scenario where I wish to model the movement of a simply supported beam under a central point load. I've done some stuff in R Studio to come up with deflection plots and that's fine. In ...
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Find deflection and reaction force of a beam using Castigliano's energy method
I want to find the reaction force of support A and also find an equation for deflection using Castigliano's energy method for this beam.
I know that the reaction force of A is 65.625 N but my solution ...
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In the context of Beam Deflections If the moment curve has a discontinuity, how do we account for it in the slope and deflection curve?
In reality if we load a beam within the elastic range of the material, it forms a curve that can be represented by a mathematical equation. But if the moment curve has a discontinuity it must mean ...
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Calculating deflections on an inclined beam
I'm applying a force to a stepped inclined beam (that's what I'm calling it; don't know what the correct technical term would be) in which it's essentially a cantilever with the first section angled ...
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Cantilever Beam Deflection under Plane strain
I have a university code that calculates the maximum deflection of cantilever beam of length, $L$ subjected to a point load, $P$ on its free end. The software assumes plane strain conditions. I ...
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Do axial displacement experiments under hydrostatic load scale linearly to any size?
In J. D. Stachiw's book Acrylic plastic viewports for ocean engineering applications [PDF] on page 337 it includes a Figure 7.12 [2] showing the results of applying hydrostatic loads to an acrylic ...
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Maximum Deflection for simply supported beam under arbitrary triangular loading
I am trying to get the:
maximum deflection
location of maximum deflection
deflection at any point
For a beam under an arbitrary triangular load (i.e. a, b, c, and w can vary). I tried to solve this ...
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Principle of virtual work "geometric proof"
I spent a full day searching for and trying to understand why in this "proof" of virtual work makes sense. I've come to understand the idea from D'Alambert's principle, but I want to ...
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deflection of mild steel hollow tube beam
I am trying to compute the deflection of a hollow tube of mild steel, and my computation seems to give radically different results than a couple of online calculators. Apparently one is in error.
The ...
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Composite Cantilever Beam Analysis
I'm trying to solve this composite cantilever beam for deflection analysis. How should I proceed? I'm not from mechanical background.
The connection between the elements is strong enough that the ...
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3
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What's the best shape (solid of revolution) for a cantilever beam to carry a point load at the free end?
How should you change the diameter/radius (while keeping constant overall volume) of the cross-section along the length of a round cantilever beam so that you minimise deflection with concentrated ...
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Deflection of Cantilever Beam with Midpoint Spring, Integration and Superposition Methods
How can I get the deflection required below using 1) the Integration and 2) Superposition methods (two ways)?
The beam $AB$ is supported by a spring $CD$, which is fixed at $C$ with constant $k$, and ...
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How is load bearing capacity of a leg of steel angle calculated?
Suppose a section of steel angle is used to support a structural beam, which would otherwise have no available bearing, as in the following sketch.
Assuming that appropriate connection/fixing on the ...
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Castigliano's theorem for deflection
Consider a prismatic bar fixed at one end and acted upon by a force P at the other. According to Castigliano's theorem we can determine the deflection of point A by partially differentiating the total ...
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Calculate shear and deflection for simply supported beam on different support height (like a staircase)?
I’m trying to calculate the beam deflection for an inclined beam. It’s only connected to floors (and not walls). The beam is a monorail and I want to test different shapes (tubes and I-beams).
Plenty ...
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Ways to stiffen a HSS profile?
I have an issue with a post that’s deflecting a little bit too much. Picture a 10 foot HSS c-channel section, used vertically as a post. Web/flange 4.5 x 1.75 @ 3/16 thick.
Clients (friends) insisted ...
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Utilizing symmetry in statics problem
I am given the structure below, and supposed to find the forces occuring in $A, F, E, D, C$ and $B$. The task hints of using symmetry, as several forces are equal in magnitude.
Supposedly, $A=B$, and ...
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How much deflection can/should I accept with Aluminum Extrusions?
I plan building things with aluminum extrusions.
On this website I can calculate the deflection depending on the profile length and load.
https://8020.net/deflection-calculator
I.e. if I select a 20/...
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How to determine beam deflection with this unusual configuration (diagram attached)
So I've got a support system shown here in the attached image. Comparing configuration "A" to "B" it seems intuitive that "A" could support a larger load. The stubs are ...
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How does the stiffness of semicircular beams connected in series increases?
I am working to reduce the deflection in a cantilever/ dive board at work.$300 mm(L) \times 30mm(B) \times 2 mm(H)$, i.e. it's a rectangular cross section currently.
I can't change the material, or ...
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Calculating the load on the end of a beam
We ordered a really nice light for our dinner table and ordered a special "lightswing" seperatly.
The light that we ordered however is heavier than the 'lightswing' is rated for.
Please see ...
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Deflection of a fixed-fixed pvc pipe under self weight
I would like to start by saying I am not an engineer, so I apologize if this question seems simpleminded.
I am making a manual tarp reel from pvc pipe, and I am trying to decided whether to use ...
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Multiple varying cross section beam with uniform loads
I have the following cantilever beam problem where I need to find the deflection of the tip at P.
I tried to compute the deflection of the beam using Castignliano' s theorem as described in this ...
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Large deflection of a non prismatic cantilever beam under distributed load
Here's what I got trying to calculate the large deflection of a cantilever beam with two different cross sections under a uniformly distributed load:
From the figure, the shear force is:
$$
V(s) = q(...
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How can I find deflection in a member that doesn't have a constant area moment of inertia?
I'm trying to calculate the maximum deflection in a simply supported member with a uniformly distributed load. The trouble is this member does not have a constant area moment of inertia. I've drawn a ...
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simply supported beam with a midspan load
First off non-engineer apologies,
A plate of 5251 Aluminium is used to support the load of a centrally seated human I estimate a load of 1 kilonewton.
The beam measures a length of 1000mm, 100mm wide.
...
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Deflection of a cantilever beam composed of separate (not bonded) planks Uniform load
This is related to this question
It is the case of a simple cantilever beam having a uniform rectangular cross-section.
cantilever beam composed of separate planks - taken from
The question in the ...
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Deflection of a rectangular plate simply supported (transverse load)
I am looking for the formula allowing to calculate the deflection of a rectangular plate with a "transverse loading in its center" (maybe the kind of loading will be more clear with this picture :
I ...
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Sign convention for deflection and slope of beam?
What is the sign convention for deflection and slope of a beam as shown in the diagram below?
When I derive the formula using Euler-Bernoulli for deflection and slope myself, I end up with - ...
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Calculate deflection of a beam with an arbitrary shape
I have a beam with rectangular cross section, but rather an strange shape in the length wise direction as seen below:
So I have taken out the symmetry part of it:
And it actually has some nice ...
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How to determine the deflection of a wire mesh under wind load?
I am trying to extend a metal wire mesh over a large distance, while tensioning it to limit the deflection of the mesh due to the wind as much as possible. After doing some research I came across ...
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Flexure Deflection - Both ends fixed (one translation free)
I have a flexure problem. One of its ends is fixed to a frame (say F1) which is stationary (no rotation & no translation) and the other end is also fixed to another frame (say F2) which can move ...
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Deflection In Multistory Structure
When analysing and designing a structure for the serviceability limit state the deflections of each beam must be found. When considering a multistory rigid jointed structure (as below) and applying ...
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What plastic material is best for a snap-fit design?
I'm designing a plastic holder that will secure a metal part with snaps. Which plastic will be able to take multiple removals and re-insertions without getting weaker (bent out of shape) over time?
[...
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How to calculate load on roller to create given deflection?
I am trying to calculate what loading on a fixed roller will create a predetermined maximum deflection. I ran some calculations, but the values I'm getting are significantly lower than I would expect. ...
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How to size a rectangular steel tube to hold certain weight?
I would like to build a shelf (1m width and 0.5m depth) using only four rectangular steel tubes on for legs.
Each legs are at the end of the rectangular tube.
I would like to put 500kg on the tubes, ...
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How to calculate the deflection of beam that is reinforced through formula?
Example an aluminium tube reinforced with steel tube inside.
100*50*2mm thick aluminium with 80*40*3mm MS tube
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Pin joint system displacement question
A pinned system comprising bars of the same material and cross-sectional area is subjected to a vertical load P.
I am required to form a relationship between FAB and P.
The first part of the ...
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Why does rebar in reinforced pre-stressed conrete reduce in deflection if compressive stress is applied to member?
According to What is Prestressed Concrete? - Practical Engineering, one way to reduce deflection in the steel rebar is to pre-stress the rebar by applying compressive stress in the member before ...
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Where is the axis of bending for a box lifted by a crane?
A box is being lifted by a crane. Sometimes the box will be completely full, and sometimes it will only be partially full (indicated by the gray shaded regions).
The question is, where is the axis of ...
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simple supported Beam deflection question involving two point loads and a UDL
so i was given a problem by my mechanical principles teacher to work out the max vertical deflection of a simply supported beam with two point loads one a distance of 5.3 away from A and another 5.9 ...
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FEA: What is the difference between a spider of RBE2s and multiple SPCs
I am not sure what the difference is between using a spider of RBE2s. and multiple SPCs across a face. I've heard that the spider is the more accurate method as multiple SPCs make the model overly ...
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Deflection of Rectangular Plate with 2 Simply Supported Edges
As shown in the figure provided, a Uniform load acts upon a rectangular plate with edges at Y = 0 and Y = b which are simply supported.
Using this form of the Plate Equation:
$\frac{\partial^4 \...
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Why do we increase the minimum beam/slab depth if we increase the grade of the reinforcement to control the deflection
I've just started to study reinforced concrete design and I came across this
in the "Design of Concrete Structures" by Dr.Nilson.
and I was wondering why do we increase the minimum thickness if we ...
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Simple beam deflection of cantilever beam
Recently I had need to prove the beam deflection equation for a simple cantilever beam with a point load at the end. The equation would be in reference to the Euler-Bernoulli theory taught in most ...
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Most efficient way for finding the rotation angles after moment distribution (Cross method)?
First of all, I have taken a look at the Grinter's method, which is similar to Cross, but balancing angles instead of moments. My question assumes that we are using the Cross method, and not the ...
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How can I calculate the maximum load of a steel box section frame?
Is it possible to calculate the maximum load of the steel structure shown in the image using its dimensions?
