Questions tagged [deflection]

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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 ...
95 views

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 ...
80 views

Derivation of beam deflection equation

I have encountered the above beam deflection equation for a beam subjected to a linearly increasing distributed load while I was solving bisection method (https://itprospt.com/qa/159961/q3-15-points-...
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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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618 views

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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1 vote
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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 ...
107 views

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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32 views

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 ...
1 vote
92 views

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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1 vote
990 views

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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1 vote
77 views

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 ...
43 views

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 ...
175 views

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 ...
1 vote
482 views

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 ...
252 views

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(...
198 views

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 ...
73 views

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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104 views

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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648 views

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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751 views

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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341 views

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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99 views

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 ...
82 views

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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3k views

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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1 vote
48 views

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. ...
60 views

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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96 views

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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280 views

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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201 views

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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1 vote
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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 ...
1 vote
174 views

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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2k views

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 \...
174 views

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 ...
1 vote
227 views

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 ...
34 views

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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1 vote
385 views

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?
2k views

Deflection of a cantilever beam composed of separate (not bonded) planks

In the case of a simple cantilever beam having a uniform shape and being loaded at its end - the calculation of the deflection at any point along the beam is well known. What happens if we split it ...
1k views

Bending equation and max deflection of UDL and multiple point loads

I have a beam, simply supported with 2 points loads and 2 UDLs. The loads are symmetric about the centre of the beam. I've tried to derive an expression for the moment along the beam and then via 2 ...
204 views

Deflection of a stack of disks under applied force/pressure

I'm trying to calculate the deflection of a stack of metallic disks, when subjected to a force. In the case of the figure below, representing a valve for a shock absorber, the force is due to a ...
1 vote
146 views

Which diameter and thickness pipe to choose

I'm building a roller for a "pool" cover I got at home. The cover weighs 10kg (8kg but I'm considering some weigh added by the water present on it). I have a bosch profile structure where I will ...
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179 views

What is the minimum diameter necessary for 2 linear motion shafts to deflect less than 0.05mm when a 2kg weight is in the centre?

I am planning to build a large scale 3D printer that will utilise 2 1000mm linear motion shafts that each have a young modulus of 210 GPA. The ends of the shafts will be secured in a block of plastic ...
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103 views

Determining the load on a pump vibration isolator

It seems to me that pump vibration isolators need to support: The weight of the pump The weight of the water in the pump The weight of the water (only) in the drop to the pump The supplier of ...
4k views

Round beam deflection under its own weight

I'm trying to calculate how much simply-supported round beams of several materials and diameters deflect under their own weight plus an additional weight in the middle. I know the material densities ...
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1k views

Structural Frame Real World Deflection

In the real world, would this pinned frame exhibit a deflection in the fixed, left hand side column? Arguments from peers largely surround: 1) There wouldn't be left-column horizontal deflection ...
43 views

Validation of Lightweight Chassis (measuring deflection of structures/strain gauging)

How can we validate the structural integrity of a small lightweight chassis manufactured from 6063-T6 aluminium that has been welded and then heat treated (back to t6 condition)? A simple FEA model ...
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How to calculate filament deflection and force applied to teeth by toothbrush bristles?

I am trying to get my head around the behaviour and the effectivity of the the filaments movement of a toothbrush inside your mouth. I want to know the mechanical formulas and/or properties that I ...
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