Questions tagged [shear]
The shear tag has no usage guidance.
82
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Metric bolt shear strength for a layman
As a layman, how can I know the shear strength of a particular size bolt?
For example, if I want to attach something to the internal wall of my van ( 1mm stainless steel ) using a rivnut and standard ...
5
votes
1
answer
776
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Is there a difference between punching shear for columns on slabs vs slabs on columns?
Might there a difference in design approach for punching shear for the two scenarios? Or something to pay particular attention to?
Is the slope of the shear plane (normally 1:1) the same for both ...
3
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3
answers
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Why does concentrated shear force on a beam influence the whole beam?
This might be a silly question but can someone explain how this shear force on the right side of the beam causes Qy throught the whole beam?
I understand it mathematically but not conceptually so I ...
3
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2
answers
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Difference between shear flow and shear stress
I have been given the following problem in one of my courses. To say that I'm struggling in the course would be an understatement... I'm just wondering what the difference between shear flow and ...
3
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1
answer
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How do you ensure that a beam is loaded through the shear center?
Reading about shearing stresses in beams, it is commonly stated that it is necessary to load a section through its shear center, so no twisting is applied to the beam. This is specially important in ...
3
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1
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Does notching the corner of an angle brace member help or hurt when shear lag is present?
Does notching or cutting out the corner of an angle brace distribute stress better along the flange of a member with shear lag or reduce the stressed edge of the flange's ability to resist deformation?...
3
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0
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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 ...
3
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0
answers
306
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Boeing 737NG pickle fork cracking. What determines the fastener layout?
Boeing 737NG aircraft are currently being checked for cracking in the "pickle fork" assembly that attaches the fuselage to the wings. The affected joint has 4 fasteners that attach the fork to the ...
3
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0
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Normal stress - shear stress pairs not lying on Mohrs' Circles
The three Mohr's circles depict all the possible normal stress / shear stress combinations when material is taken and rotated along one of it's axes of principal stress. Nevertheless, it is clear that ...
2
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3
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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
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3
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907
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Difference in shear stress - one bolt vs two
So i have a little diagram to visualize:
So lets say i have a 20 mm plate connected with two M8 bolts, and i apply a 30kN force in the direction shown in picture. Question is - would the force be ...
2
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1
answer
648
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What is the difference "maximum" shear stress and shear stress
Shear stress is introduced in statics as $\frac{P}{A}$.
However, the maximum shear stress with neutral axis is different. It is $\frac{3P}{2bh}$ (Where $b$ is width and $h$ is height)
What is the ...
2
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2
answers
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Maximum shear force of metric steel bolt
I'm struggling to calculate with any confidence the allowable shear force for a metric bolt holding two aluminium pieces together.
I only need an approximate figure, since I will allow a very large ...
2
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2
answers
1k
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How do you calculate the shear force on the screws that connect a door to a jamb via hinges
I'm trying to calculate the shear forces on hinge screws or bolts. Here is a schematic of the door with the relevant values:
First, I took a free body diagram of the door and its hinges. The ...
2
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2
answers
3k
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Determining when bolt will bend
I'm attaching a metal pipe to a metal tube as shown in the below diagram. The bolt is threaded through one wall of the pipe and does not pass through the opposite wall of the pipe, but is tightened to ...
2
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4
answers
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What is the difference between tau = VQ/It and tau = V/A?
What is the difference between the formulas $\tau = VQ/It$ and $\tau = V/A$ for finding shear stress due to transverse loading? I understand that the use of first moment of area, is the only reason ...
2
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1
answer
335
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Failure due to shear stress on rod lip?
Let’s say I have a circular rod that has an outside lip with a larger diameter and certain height. The rod moves axially, and the intent of the lip is to mechanically stop the rod at a maximum axial ...
2
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1
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Is the calculated shear strain in a beam, engineering strain or tensorial strain?
Recently I came across a FEM code of a linear deformation beam element, and it made me wonder what is the correct relation between shear stress and shear strain in a beam element.
In the beam element ...
2
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0
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532
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Double Shear Stress butt joint
A double shear butt joint is shown below in the diagram 4 plates are held together by two bolts. The applied force is 42KN. Determine the shear stress within the joint
$$\begin{align}
a &= 2 \...
2
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0
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Regarding the ITTC Guidelines for Ship CFD applications
I was reading through the ITTC – Recommended
Procedures and Guidelines - Practical Guidelines for Ship CFD Applications (https://ittc.info/media/4196/75-03-02-03.pdf) document and this little thing ...
2
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0
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What degree of open span/narrow support can rigid PIR thermal insulating foam sustain under the short term load of setting concrete?
I've found data related to the deformation and shear performance of typical PIR (polyisocyanurate) foams such as Celotex/Kingspan, but I'm not sure how to use these figures in my own situation.
I am ...
2
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0
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How to consider shear forces in CEB/fib 2010 three-layer model for concrete slab design?
I have a question about design of concrete shells with three-layer method described in p.7.3.2.2 fib Model Code for concrete structures.
The main idea of method is that we divide shell on three layers....
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3
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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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2
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894
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Why torsional warping does not occur for shafts with circular symmetry?
When we twist a shaft/beam/rod, shearing stresses are produced. The angle by which the end of the shaft rotates can be found as:
$${\displaystyle \theta ={\frac {TL}{GJ}}}$$
where $T$ is torque, $L$ ...
1
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2
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224
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What is the difference between max shear stress at neutral axis in bending and max shear stress from Mohr's Circle?
The maximum shear stress which we get from the equation: $\frac{VQ}{It}$ (for instance, the maximum shear stress at the neutral axis for a rectangular beam cross section, fixed at one end and ...
1
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2
answers
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How to calculate failure stress on a hollow pin loaded in shear
Calculating limit stress on a solid pin loaded in shear is straightforward, and there are several handy calculators which will do single shear and even double shear. However, everything I have found ...
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2
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6k
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Determine shear flow direction in profile/beam section
I have been looking at the location of shear flow centers for profiles for my mechanics of materials course.
I am trying to figure out how to determine the direction of the shear flow in a given beam ...
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3
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254
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How to use Mohr's circle to find stresses on a slanted plane?
Here is my attempt to the problem:
Does this make sense? rotation clockwise 60* from horizontal to normal of the slanted plane , therefore $2 \times 60$ clockwise as well on Mohr's circle.
I am ...
1
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2
answers
61
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How to find the shear stress just below or just above some elevation?
Say the cross section carries a vertical shearing force of 40 kN. And say I want to find the value of the shear stress just below the section a-a.
I am very confused about which area $(A)$ to take ...
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1
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240
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Connection for beam very close to concrete wall
The following picture is pretty self-explanatory. I need a connection for a beam that is coming in very close to a concrete wall edge (north/south beam in picture). The embedded plate with nelson ...
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1
answer
880
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Shear strength of reinforced concrete filled PVC pipe
BACKGROUND: I'm burying a 3 foot x 4 foot drainage box (2 foot tall) in my driveway to hold/distribute excess gutter flow (1" of rain produces ~21cuft). I've constructed the walls with brick, laid on ...
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2
answers
101
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How to improve the shear strength of a steel rod?
How can the shear strength of a steel rod be improved? The application I am thinking of is rods used to make bolts where we want the bolt to resist being sheared off after it is attached.
Some of the ...
1
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1
answer
438
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Maximum shear in a beam
Engineering books and lectures typically make two things clear:
Maximum bending stresses (normal) develop at the beam surfaces, that is, at the greatest distance from the neutral axis.
Shear stresses ...
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1
answer
174
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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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1
answer
50
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Calculating the diameter of screws that are on radius 160mm from axis of rotation. I need help - I don't know If I'm thinking in the right way
First of all, english is not my first language so if there are some mistakes I made - I'm sorry and I hope everything is understandable.
The example I am trying to solve reads the following:
The gear ...
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1
answer
212
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Physical Significance of Max Shear Stress in a Rod in Compression
For a rod in compression, the max shear stress at a point is $\pm\sigma_x/2$, i.e. half the compressive stress applied at either end.
This value is obtained using the equation for $\sigma_\theta$, ...
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1
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444
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Shear force and bending diagram un-uniformly distributed load
I already got great help on this topic, but I'd like to make sure that I get it.
For example, take a beam of length 6 meters, left side fixed support and right side rolled support. There is a load of ...
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1
answer
28
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Maximum tensile and shear loads on screw
I'm using a screw in an application where I want to have a high degree of confidence the screw will not fail, and I want to be sure I'm calculating the maximum tensile and shear loads it can sustain ...
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3
answers
263
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What does negative shear stress mean $\tau \:=\:\frac{VQ}{It\:}$?
$\tau \:=\:\frac{VQ}{It\:}$
My confusion lies within $Q$ term. $Q = yA$ where $A$ is the cross-sectional area of the segment that is connected to the beam at the juncture where the shear flow is ...
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1
answer
28
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should the hachures in moment and shear diagram be vertical?
when we plot the shear or moment diagram we add hachures to the area created with these diagrams , in most cases we see vertical hachures, is it represent the internal forces? or its just used to ...
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1
answer
106
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How to find the reaction at the pinned support A as shown in the picture? [closed]
Please help me solve the problem. I need to know the reactions at A for both the cases as shown. Please note that E is a roller, D is a pin support , B is an internal hinge and A for case 2 is a fixed ...
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0
answers
157
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Is Viscosity = Slope?
studying fluid mechanics, I see that viscosity relates shear stress to shear rate, like a slope. However, on graphs I see that they draw a triangle, and where I would expect to see $\Delta \tau $, I ...
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2
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Shear Wall Boundary Element
When can I design a boundary element of a shear wall as a column?
Is there a link to a solved example?
Help please.
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2
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How can I describe cold work and atomic structure?
A copper wire (42 cm x 0.25 cm diameter) twisted to failure did not change its dimensions significantly. How can I visualize or quantify the cold work done (tensile at the exterior, compressive in the ...
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0
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37
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Shear modulus in terms of 2 Young's moduli and Poisson ratio
I have two moduli, EY and EZ, and the poisson ratio NUYZ, and the equation for the shear modulus that I am using is
$G = \frac{EY*EZ}{EY+EZ+2*EY*NUYZ}$
but I am not sure where it comes from.
I tried ...
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0
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15
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Shear between which two fluids is better for atomisation - liquid & liquid or gas & liquid?
In designing an atomizer which generates a spray of liquid, one can adopt atomisation through shear.
Shear in the following cases are to be considered:
stagnant Gas- moving Liquid: in this gas case ...
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0
answers
41
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Influence of shear force on pressed part with steep walls
I'm working on a project that involves pressing a softened thermoplastic sheet in a two-part mold to form a part 0.090" thick. None of us at our small company are experts in matched molds, and we've ...
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0
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100
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Calculating stress from elementary tension and bending formulas
I need help with this problem.
Suppose we have a cantilever with width $-c \leq y \leq c$ and length $x=l$ fixed at $x=0$. We know that it is loaded by uniform shear along the lower edge with ...
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0
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222
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Distribution of shear stress in beam bending
Beer, Johnston, and DeWolf's Mechanics of Materials includes the following image of the distribution of shear stresses in a bending beam: (Axes and load vector carried forward from Fig 6.1 in the text ...
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4
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Why does a beam in shear crack at 45 degrees?
Why does a beam in shear like in this picture crack at 45 degrees instead of vertically? This is called "Punching shear", and requires concrete reinforcement at an angle:
Assuming that the ...