Stress Definition and 1000 Threads

Hello to everyone, I have a problem with the solution of plane elasticity problems with the method of Airy stress functions. For instance I can solve a problem of uniaxial or biaxial uniform tension with a 2nd order polynomial, but if I add shear on only two opposite sides the problem seems to...

Homework Statement If I consider a force, which is applied to both ends of a rectangular beam to its cross section with dimensions w (width) and h (height) and I know the length of the beam is l and the force is parallel, how can I calculate the stress? Also, what if the force were parallel to...

I am having some trouble finding out the Maximum shear stress, I worked out my hoop stress and axial stress for the thin cylinder theory but the radial stress i am having issues with. If the applied pressure is only internal then would the radial stress be 0.

intuitively it makes sense but what is the scientific explanation

[FONT=PT Sans]how to get the formula of shear stress (tau) ? i got (-dp/ds -ydz/ds )(r/2) instead of -d(p+yz)/ ds (r/2) as in the book , if it's d(p+yz)/ ds (r/2) m , i would get (-dp/ds -ydz/ds-z(dy/ds) )(r/2) ,, right ? The Attempt at a Solution P/s : I'm concerned about the derivation part ...

How does one setup the stress tensor for a non-Newtonian fluid? I know that for any fluid the normals should be the pressure and for a power law fluid the shear stress in the direction of flow is related by K(du/dy)^n. Does this mean that all other components are 0 for a symmetric pipe or...

Homework Statement I am having trouble decomposing a uniaxial compressive stress into hydrostatic and pure shear components. Homework EquationsThe Attempt at a Solution I am starting with ## \begin{pmatrix} -\sigma & 0 & 0 \\ 0 & 0 & 0\\ 0 & 0 & 0 \end{pmatrix} ## I then do ##...

The problem: The stepped bar with a circular hole, shown in Figure P5.75, is made of annealed 18-8 stainless steel. The bar is 12-mm thick and will be subjected to an axial tensile load of P=70kN. The normal stress in the bar is not to exceed 150 MPa. To the nearest millimeter, determine (a)...

https://www.google.ca/search?q=stress&biw=1366&bih=629&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjA9u3S5_jKAhXCJx4KHfN8DmYQ_AUIBigB#tbm=isch&q=stress+tensor&imgrc=xK8-tGSPxXha7M%3 This is a simple question. -why stress is defined on 3 surfaces only instead of the entire 6 surfaces? I believe 3...

I need to know why the Engineering stress increases after reaching the yield stress point, and continues to increase until reaching the UTS. Am I correct when I remember that there is strain hardening that occurs along the region from Yield stress to the Ultimate tensile stress? Engineering...

Homework Statement A flat part with constant thickness b is loaded in tension as shown. The height changes from 50 to 87 mm with a radius r = 4.0 mm. Find how much lower a load can be transmitted through the bar if the height increases from 50 to 100 mm and the radius increases from 4.0 to 10...

Is the maximum bending moment and maximum shear stress an absolute value? For example, when drawing out a bending moment diagram say if I get -400 kNm at one point and 300 kNm at a different point. If these values are the maximum/minimum points on my diagram would 400 kNm be considered as a...

Homework Statement Homework Equations δ = Pl/AE σ = P/A The Attempt at a Solution I had calculated the deformation for both the steel and aluminum, and added them together to give me δ = 0.481 mm, which is incorrect. I also thought I could simply plug in the force P = 200kN and the...

I usually come across expressions for the Stress energy tensor showing them as three densities (normally over a space-like slice. In wikipedia's article on the spin tensor, they clearly (it does not appear to be an error) both write about and express the components of the stress energy tensor as...

Hi, I would like some guidance about a piping problem I have. I would like to know how to solve this shear stress equation for a narrowing pipe. This equation gives the shear stress on the edges of a cylindrical piece of fluid having radius r and length L within the pipe. I would like to know...

Homework Statement how to make μ = ρ v as in 8-41 ?Homework EquationsThe Attempt at a Solution since μ = viscocity , it has unit =( kgms^-2)s m^-2 , = kg(m^-1)(s^-1) ρ v = (kgm^-3)(ms^-1 ) = kg(m^-2)(s^-1) , the unit for LHS and RHS are not the same , can someone help pls ?

For 3 D loading with shear, if I use the principal stress formula, say for x-y direction, two principal stresses are obtained. If the same is applied to y-z, two more principal are obtained, with one supposed to be common, but not. Thus I obtain six principal values, which cannot be used with...

Hello all, I am a new member of PF.I have a basic question about the bending stress, I remember somewhere I saw this part, but can't find out it. Could you give me a answer? Given: 1, M-moment applied on the section. 2, I-Section modules 3. y-distance from shear center Solution F,how much is the...

Homework Statement for the second photo , why the dy is 0.005/2 ? why not 0.005 ? Homework EquationsThe Attempt at a Solution

Homework Statement Write down the expanded form of the stress power SigmaijDij in the case of a general three dimensional state of stress, a two-dimensional state of stress, a uniaxial state of stress, a state of simple shear , and a spherical state of stress. 2. Homework Equations [/B]The...

Hi, I'm doing question (c)(ii) in the image below, full working is provided below: (c)(i) is 150kPa. I = bh^3/12 - 2 * bh^3/12 (0.25 * 0.256^3)/12 - (2* (0.119 * 0.22^3)/12) = 1.3831 x 10^-4 m^4 Q = y*A = 0.119 * 0.018 * 0.250 = 5.355 x 10^-4 m^3 shear force = (150000 * 5.355 x...

I'm in college working towards a degree in Mechanical Engineering, so far I've only made it through physics 1 and calculus 2, but I've been building race cars and pulling trucks and tractors since i could hold a wrench. I work for a guy that builds super modified four wheel drive pulling truck...

Hi, I'm struggling with finding the tensile stress at the mid-span of this beam. I've done the previous questions but have no idea how to begin with this one as I've never dealt with this question before. What is the general method? Correct answer is 1.66MPa. Thanks.

Orbiting bodies are often stressed and twisted by the tidal forces of the larger body. My question is, if these stresses cause the planet to heat up then what system provides the energy to do this? Does the larger body lose energy? Can the gravitational field act as a medium for energy exchange?

Having trouble figuring out how to link the two Young's Moduli to the Bending Moment, any suggestions?

hi guys i've really been struggling with this question but I still can't get any glimpse of idea on how to solve the problem, so the conditions are given in the table and what the question is asking for is the axial force acting in each members of the structure. ah, almost forgot to tell you...

I just can't figure this out with the stresses and moments. What is the force required on the handle to get the 850N on top? Link to album: goo.gl/FYpc0k

Homework Statement A rule often used in shaft design states that the angle of twist shall not exceed 1° on a length equal to 20 diameters. What stress in the material does this imply if the modulus of rigidity is equal to 80 × 103 N/mm2 ? Homework Equations T/J=Gθ/L=τ/r J=π?32(D^4-d^4)[/B]...

A rule often used in shaft design states that the angle of twist shall not exceed 1 on a length equal to 20 diameters. What stress in the material does this imply if the modulus of rigidity is equal to 80 × 103 N/mm2 ? was wondering if anybody had an insight on how to do this ? have tried a...

I'm making a robotic structure using hydraulics and pipes, and I need to choose what size pipe and thickness I will be using. I've searched online to the best of my ability but all I got were equations for I-beams. I've taken statics in college so I know how to calculate all the loads in a...

Hi, Am I right in saying that if the gradient of displacement is negative then stress is negative as in a simple elastic case, sigma = E*du/dx? thanks.

Homework Statement Hello guys, I have to calculate the shear stress in this figure. The sizes are: a = 250mm, b = 100mm, c = 250mm, d = 150mm and t = 10mm. The shear force working on it is Vcd = 39802.01 N (calculated before) The center of the construction Nc is at 157.95 mm (from the...

what are the equations to measure attenuation, frequency, amplitude of a stress wave propagation of metal rod or plate which is immersed in water or fluid?

Homework Statement Member AD of the timber truss (shown in attachment) is framed into the 100 x 150 mm bottom chord ABC as shown in the insert. Determine the dimension "a" that must be used if the average shearing stress parallel to the grain at the ends of chord ABC is not to exceed 2.25...

Hello this is my first question here :) So here is my problem: We have a circle radius 50 (m), made out of iron wire mass 5.506206591207348477884587 Kg per meter of rope. Rope diameter 11/8 inces or 3.4925cm The wire rotates with 3 rpm in zero gravity 1)How can i calculate the tension? Thx...

Homework Statement Homework Equations The Attempt at a Solution I'm trying to find the principal strain, then from that find stress. The poisons ratio should be around 0.3 for this experiment. My result is about 100 micro strain higher than what my class mates got. Can anyone see...

I have to model a storage vessel in ansys and perform stress analysis for it. I have no idea about which element types I will need for the analysis. I have calculated the design dimensions for the vessel. I am a beginner at ansys and know only how to deal with simple structural and thermal...

Hello guys, I have a simple question about the max bending stress in a beam. We know that in a cantilever beam, the biggest moment occurs at the wall. This is also the location of the max stress with equation stress= M*y/I , However, in a simple supported beam, we have This time, the max...

Hi, sorry for my bad english. PART A I have a cube of 10mm x 10mm x 10mm which is compressed with a stress of 0.5 Mpa on his superior face (σz=-0.6) young modulus=20Mpa, poisson coef=0.5 I have the stress tensor: [ 0 0 0] [ 0 0 0] [ 0 0 -0.6] And then, the deformation tensor is : [0.015 0 0] [...

Homework Statement Homework Equations Young's Modulus, E=σ/ξ Stress,σ =F/A Strain, ξ=x/L The Attempt at a Solution As diameter and tension are constant, so stress must be constant I assume.. So for the same Young's modulus, if stress is halved, then strain must be halved too I guess. But I...

We have a cube with sides of 10mm (fig a) (in the same material than the exercice 1 (have poisson coef & young's modulus) A- figure A 1- Write the stress state and the relatives values deformations (tensor) 2- Why the sum of relatives deformation is equal to 0? B-Figure...

1. I'm given time (s), extension (mm), tensile stress (mPa), and tensile strain (%) in a table. I'm supposed to graph it on excel, but my graphs don't look at all like a stress-strain graph. 2. I think it's probably because I'm using tensile stress or strain? Or is it an excel error I'm doing...

We know that when two equal forces act in opposite direction they nullify each other. But when two equal forces act on a body yet it deforms eventhough the resultant force is zero? Can you explain how the stress is created and results in longitudinal strain?

I am having the hardest time calculating q, the load per unit length. This question is in relation to my previous question I posted here. I have a cylinder laying horizontally that is fixed on its ends. The cylinder is filled with water. To calculate the deflection I am simplifying the problem...

I am having some problems understanding how to apply a distributed load to a cylinder due to it being filled with water. Attached is an image of the cylinder (placed horizontally). The cylinder is symmetric about the y axis. Water is to be filled from the left through the 1" hole. The cylinder...

Hi I was wondering how you would account for mean stress (such as using with goodman equation) using von mises with miners rule due to variable loading Thank you

What determines the sign/direction of shear stress arrows in Mohr's circle? Please see pictures below. Why are the shear stress arrows drawn the way it is and not in the opposite directions?

Homework Statement In a certain system of units the electromagnetic stress tensor is given by M_{ij} = E_iE_j + B_i B_j - \frac12 \delta_{ij} ( E_kE_k + B_kB_k) where E_i and B_i are components of the 1-st order tensors representing the electric and magnetic fields \bar{E} and \bar{B}...

Question is as follows: We have a single crystal of Al in a tensile tester. WE are applying a tensile stress, [δ][/Ψ] perpendicular to the 212 plane and we have found that slip has occurred. What is the shear stress that produced the slip? not sure how to proceed, first thought was use the...

Homework Statement A series of shear tests were performed on a weak rock. Each test was carried out until the sample sheared, and the principal stresses for each test were: S. No.--- σ3 (KN/m2) --- σ1 (KN/m2) 1 --- 200 --- 570 2 --- 300...