Questions tagged [deflection]
The deflection tag has no usage guidance.
41
questions
2
votes
1answer
35 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?
[...
1
vote
0answers
31 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. ...
0
votes
1answer
39 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, ...
0
votes
1answer
32 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
0
votes
2answers
56 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 ...
0
votes
2answers
41 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 ...
1
vote
2answers
68 views
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 ...
1
vote
1answer
48 views
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
1answer
47 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 ...
0
votes
1answer
158 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 \...
2
votes
1answer
25 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
0answers
182 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 ...
2
votes
0answers
28 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 ...
1
vote
1answer
93 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?
1
vote
2answers
450 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 ...
2
votes
1answer
321 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 ...
2
votes
1answer
65 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
1answer
81 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 ...
0
votes
3answers
78 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 ...
2
votes
0answers
62 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 ...
4
votes
2answers
2k 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 ...
2
votes
4answers
614 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 ...
0
votes
1answer
38 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 ...
3
votes
1answer
185 views
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 ...
0
votes
1answer
1k views
What is the formula for deflection of an end-loaded cantilever rod beam?
For a cantilever beam of circular cross section, loaded at the end, how does the deflection of the free end vary as a function of beam length and diameter?
I expect the answer will be something like:
...
1
vote
2answers
178 views
Why does a simple pin-ended triangular (arched/curved) beam deflect more due to secondary effects (non-linear analysis)?
I cannot wrap my head around this.
I have made two simple models, a triangular (or curved or arched) beam that is pin ended and has a single point load of 1N downwards at it's center, and a flat beam ...
1
vote
0answers
38 views
Countertop Span/sag Calculations [closed]
I came upon enough 3"x3" structural aluminum square tubing to build a countertop over the washer, dryer, and sink. I wanted to double check the sag/deflection of the tubing but am having trouble ...
-2
votes
1answer
2k views
How can we know “by inspection” the location of maximum deflection of a simply supported beam with a point load?
I am working the following problem:
The simply supported beam shown in Fig. 12-12a is subjected to the
concentrated force P. Determine the maximum deflection of the
beam. EI is constant.
...
1
vote
1answer
982 views
How to calculate deflection of a cantilever beam subject to point loading
I am trying to solve the following beam deflection problem:
The cantilever beam is subjected to the point load at C.
Generate the equation for the elastic curve by using the double ...
4
votes
2answers
128 views
Undesired vibration of a beam under foot traffic
The other day I was in the waiting room of a doctor's office in a new building as part of UCLA medical complex. A new construction as part of multi million dollar extension of existing medical complex ...
5
votes
1answer
74 views
Can the thickness of a guard post be derived purely from energy principles?
Consider an ordinary staircase with a banister rail supported by a wall at one end and a steel post of constant profile at the other end. The base of the post is embedded rigidly in the fabric of ...
4
votes
3answers
783 views
Deflection of thin plate with 1 free edge and deflection > thickness
I have an thin uniform rectangular steel plate supported on 3 sides and free on one, and supporting a uniform load.
I'm trying to determine what thickness of plate I need to keep deflection below a ...
4
votes
1answer
2k views
Deriving the deflection force equation for a beam that is fixed on both ends
I want to calculate the force-displacement equation for a beam that is fixed at both ends. I think I should use the superposition principle but I am not very sure how to get started.
I know that for,...
1
vote
1answer
909 views
How determine the compression of a beam with a concentrated end load in the x axis?
I'm studying Electronics Engineering so I have almost no background in mechanics, just a little of statics and dynamics. I have recently started an internship in an investigation center where they ...
2
votes
1answer
852 views
Maximum deflection of a beam with both ends fixed and distributed load
I'm designing a part, and I'm trying to figure out what distance a slot should be from the bottom of the part. For simplicity in analysis, I'm approximating the region between the bottom of the slot ...
1
vote
1answer
559 views
Breaking strength of stainless steel bar
I'm considering attaching a stainless steel bar on a sailboat masthead.
My initial thought was to use a bar with a cross section of 3/8x2" and 1/4x2". The bar will be supported for 3" of its 5" ...
9
votes
1answer
2k views
How should a bridge deck closure pour be positioned?
The Question:
Where should a closure pour be located relative to centerline of girder and how should the closure pour width be detailed/designed?
And now, a little background:
When designing a ...
3
votes
3answers
938 views
How is shelf deflection determined?
Question: How is shelf deflection determined? More specifically, how is the deflection determined when one or more edges of the plate have reinforcing edging applied to them?
I have been able to ...
9
votes
1answer
3k views
What is the effect of end diaphragms on prestressed girder forces/deflections?
I'm encasing the abutment ends of prestressed concrete bridge girders in concrete before the deck pour. (For lateral stability and to prevent the soil from spilling through.)
Discussion of ...
3
votes
2answers
452 views
Should long-term prestressed girder camber always be upward?
When considering long-term prestressed girder camber (for a bridge), what are the implications (if any) of long-term downward deflection on girder performance? Should prestressing be designed to ...
2
votes
0answers
63 views
What is the load response of a threaded fastener?
Due to the fact that pipe flanges rely on bolts, and bolts rely on friction, it seems obvious to me that in deflecting to meet the load, the nut will immeasurably turn. So my question is - how much?
...
