Stress Definition and 1000 Threads

Hey all, So I have this beam problem and I honestly am lost with it! The beam is I-section cantilever, tapers in depth along its length (See picture attached) with a point load at the free end. I am trying to figure out the deflection formula and how to derive it! Also, when calculating its...

When one substitutes the angle -23.7 into the plane stress transformation equation for SigmaX' you indeed get -46.42 MPa (as shown in the images). However, if you substitute this same angle into the plane stress transformation equation for SigmaY', you yield the other principal stress of 116.4...

Dear Colleagues, This problem causes me a headache - any suggestions? I have a truncated cone under bending on two axes. I take a section where I have two acting side forces - Qx & Qy I want to find shear stresses acting in the point A which is on a circumstance of the section 45° between axes...

Homework Statement For a crystalline metal material - Elastic modulus E - Poisson ratio v - A table with test data of stresses vs. total strains, from a monotonic uniaxial tension test, which generates a stress-strain curve. How would you use this data to find the corresponding pure shear...

Hi, I have two squeeze balls with pressure sensors inside them. One squeeze ball(Ball A) has a sensor placed at the center while the other one(Ball B) has two sensors, placed very close to the two opposite surfaces. These squeeze balls act as an input to a game developed. Depending upon the...

Homework Statement Determine the state of stress at point A on the cross section of the beam at section a−a. TakeP = 33kN . Homework Equations σ = My/I The Attempt at a Solution Moment = Fd = 33000N(500mm) = 165000000 Y = 90.71 (100-9.29, 9.29 being the Ybar of the little piece) I =...

Hello, I'm currently in the middle of my graduate studies in medical physics (first year of Master's degree). The program has a reputation among past M.Sc. students of having a very demanding first year in terms of course content. While I'm having success in terms of GPA (3.8 last semester)...

Hi all, It's my third year of college studying mathematics. Some of the upper level courses are more challenging, although I'm making it through them. After school, I want to get a masters or PhD in mathematics. I currently work 10-15 hours a week, and sometimes this adds a lot of stress...

Homework Statement Determine the state of stress at point A on the cross section at section a−a of the cantilever beam. Take P = 350kN . Homework Equations Um . . . σ = P/A ? The Attempt at a Solution Yeah I'm not quite sure. I thought it was P/A, using 350000N as "P" and 300000mm^2 as A, but...

I need help understanding a passage in my textbook, where the form of hookes law in continuous elastic media is explained. It says: "The absence of internal directions in isotopic matter tells us that there are only two tensors available to construct a linear relation between the the stress...

Homework Statement A dog-bone specimen made by aluminum alloy is used for tensile testing by a force of 4000N via two steel pins. The dimension of the specimen is shown in the following picture; the thickness of specimen and the length of pins are 4mm and 8mm, respectively. The mechanical...

I would appreciate any help with the following question: I know that for relativistic field theories, the stress tensor can be obtained from the classical action by differentiating with respect to the metric, as is explained on the wikipedia page...

Hello So I've done some calculations, I'd like to see if my stuff is right. Thanks :) Please view attached http://i.imgur.com/AfMZyr0.jpg area = (pi)(9^2) = 254.46 Cos53.13=15/CG CG=25kN Normal stress = 25000/254.46 =98.25

Homework Statement I've used all the proper equations and done all the work with no problem. My only question is when computing the maximum stress, how do I know which one is the tensile and which on is the compressive? I've attached all my work and came out with Max stress = 3.84 Mpa and Max...

Homework Statement Homework EquationsThe Attempt at a Solution I can't understand the solution and what is the variable "X" !

Hello all, I have a homework question that I am almost 100% sure that I solved, so I do not believe that this post should go into the "Homework Questions" section. This thread does not have to do with the answer to that homework question anyways, but rather a curiosity about whether or not this...

I am doing FEA analysis using Abaqus and I need to get the average/min/max Von Mises stress for a section rather than the Von Mises stress for each individual element. I have tried using python scripts such as http://www.eng-tips.com/viewthread.cfm?qid=184288 however I have had no success as of...

Homework Statement For reasons based on cost,weight,availability , etc., the choice is made to construct the rod from aluminum of σall = 100 MPA. What is an appropriate choice for the rod diameter ? Givens: (P=50 KN) Homework EquationsThe Attempt at a Solution σall=P/A , then he get the Area...

This isn't a homework question. I just have a thought I'd like an answer to. When I think of a bending beam it's obvious to me that the point on that beam which is under the most stress would be the center ( assuming equal loads on each side). my question is what is the scientific explanation...

MODERATOR NOTE: THIS THREAD WAS ORIGINALLY IN ANOTHER FORUM, SO THERE IS NO TEMPLATE. I have a hollow shaft made of a titanium alloy, Shear Modulus "G". The shaft has a wall thickness of 3.2mm and an inner diameter of 20mm. The shaft looks as show in the attached image. A torque T of 232 Nmm...

Hello. I know what follows seems like a HW problem, but it's an actual problem I'm trying to solve with some equipment I will be using. I am concerned that a bolt I am using will be unable to withstand the forces that it will face, and so I am trying to solve the problem out mathematically as...

Hi, everyone. I am learning fluid mechanics. One book says that for a infinitesimal fluid cell, surface force includes 1) the pressure, which is imposed by the outside fluids surrounding the concerned fluid cell 2) the shear and normal stress, which result in shear deformation and volume...

Determine the tensile stress in the bolted connection shown below for the load F = 210 kN. Using a safety factor of 2, determine whether the plates will fail or not if the yield strength of the plate material is 270 MPa and the thickness of the plate is 12 mm. The nominal diameter of the bolts...

The equation for shear stress as I know it is VQ/It where V is the shear force, Q is the first moment of area(?), I is moment of inertia and t is the length of the section in question. My question is, is there a general formula for Q? In my Solid Mechanics notes I've written that Q = ∫y.dA but...

Homework Statement Rigid beam ABC is supported as shown in the figure. The pin connections at B, C, and D are each double shear connections, and the ultimate shear strength of the pin material is 640 MPa. Tie rod (1) has a yield strength of 350 MPa. A uniformly distributed load of w = 11 kN/m...

Homework Statement My textbook says that the state of plane stress at a point is uniquely represented by two normal stress components and one shear stress component acting on an element that has a specific orientation at the point. Also, the complementary property of shear says that all four...

I want to know the maximum shear stress acting on the y-z face(plane). I already know all 6 stress components: Sxx, Syy, Szz, Sxy, Syz, Sxz. The shear components on the y-z face are Sxy and Sxz, which are orthogonal to each other. Is the maximum shear on this plane simply the greater of the two...

HI everybody I am in dire need of help. I have started a mechanical systems module as part of a distance learning foundation degree. The notes seem quite sparse to me and I can't seem to get to grips with it from the start. I have attached a photo of the tutorial questions but the are no...

I am so confused about these quantities. For many theoretical setups you assume a linear relation (elastic materials) such that for example if you press on the side of a rectangular box, it makes the box contract in the normal direction to the induced stress. Also the box will expand in the...

Homework Statement Hi Everyone, I am going to be doing an experiment soon using strain gauges on a beam and I will have to, among other things, calculate the direction of the maximum shear strain with respect to the axis of the beam. I am trying to find the correct equation to use. Homework...

How can we determine which curve has larger slope just by looking at curves. http://www.meritnation.com/img/shared/userimages/mn_images/image/a_2_12_2.png Which curve has larger slope?

Homework Statement a duralumin rod of 50mm diameter is a loose fit inside a mild steel tube of 60mm outside diameter. if the steel tube is turned down to 55mm diameter over one half its length, calculate the stress in the duralumin rod and the stress in each portin of the tube due to an akial...

Homework Statement A 2.75 KN tensile load is applied to at test coupon made from 1.6 mm flat steel plate (E=200 GPa, v=0.30). Determine the resulting change in the 50 mm gage length. Homework Equations εx = (σx/E) + (-Vσy/E) - (Vσz/E) εy = (-vσx/E) + (σy/E) - (Vσz/E) εz = (-vσx/E) - (Vσy/E)...

Hello all, I've got stuck with building a test rig for my PhD. I'd like to design a pressurised chamber with a window on. The temperature of the chamber and window will rise up to 500-600 C deg. I can calculate the stress in the window but I can not find any info on the ultimate...

I had a discussion with someone who studies psychology recently and she was referring to mental stress as of what I thought being called physical stress. Namely while she was talking about mental stress she mentioned stressors and hormones. So my problem: Stress = tension Physical =...

Homework Statement If \sigma_{ij} = \begin{pmatrix} 3 & 3 & 3 \\ 3 & 3 & 3 \\ 3 & 3 & 3 \end{pmatrix} represents a stress tensor, on what plane(s) will the normal stress be a minimum? On what plane(s) will the shear stress be a maximum? Homework EquationsThe Attempt at a Solution The first...

Homework Statement A certain type of concrete has a tensile breaking stress of 3.1 MN/m^2, a compressive breaking stress of 37.7 MN/m^2 and a shear breaking stress of 9.4 MN/m^2. A circular pillar of this concrete has a radius of 0.6 m. What is the maximum load it can support assuming that it...

Homework Statement A steel pipe is 200mm internal diameter and 20mm thick. Calculate the safe internal pressure if the allowable stress is not to exceed 140Mpa. Homework Equations σr = A-B/r^2[/B] and σtheta = A+B/r^2 The Attempt at a Solution Right so, I've got two equations...

Homework Statement I need to find thermal stresses that will be produced in a tank barrel as a result of firing. First of all, I want to know if theses stresses can be small enough to be neglected? And if not, then how can they be calculated? I basically know the solution but I want to be sure...

Hello Folks, May be I am bring up the old topic again., but I've lost enough sleep over this topic. I understand that we use Von-Mises criteria for ductile material failure by comparing to yield limit and max principal stress is used to check failure for brittle materials. My question is bit...

Homework Statement For (fi)= (b/6) x*y3 +C*xy show that simply supported beam of 2L loaded concentrated load at mid span.,the stress function satisfy loading condition is (fi) .treat concentrated load as shear stress suitably distributed to shoot this function. so that intergtal of limit (h to...

Homework Statement jan 2012 q3.jpg I've solved everything up to part d). I generally struggle with questions on bolts and I'm really not sure how to tackle this problem. Homework Equations τ = Tr/J, τ = 200MPa, T=1kNm The Attempt at a Solution I worked out the separation of the bolts (I...

Hi guys, Quick question, How do you calculate the min. weld thickness needed for an allowable stress? You calculate shear flow I assume? Thanks in advance!

I'm doing a little project which came to a stop. I calculated expected material stress to be ~10 MPa. (bending) I know that my material (AlMgSi0,5) should carry well that stress, however I'm interested in max allowable stress for this material...

Homework Statement If I have two spars running through an airfoil, which can be assumed to be two dimensional, which method would I use to find the stresses at the points where the spars are fixed? The loads would be lift and drag and what I need are the bending and shear stresses. Because I...

To makes things simple, consider a simple beam fixed at one end an a load applied at the other. This load will produce shear stress, bending stress, and torsional stress. When looking at yield at the fixed end, do I take the biggest stress of the three or do I add their magnitudes to see if it...

Dear Friends, Merry Christmas to All. I am pleased to join this forum of Physics Experts. Please advise what is difference between tensile Strength and Bending Stress of Metal Sheets (Generally below 3.00mm and lighter). I very often encounter with cracking of steel sheets while bending in...

I need to find the impact force that can be absorbed by these spacers as shown in the image. The spacers are radially distributed over the shell, and they are supposed to dampen any external impact loads to reduce the effective stress inside the inner shell. Since the FEA model is not showing...

Homework Statement Two wires are made of the same metal but have different dimensions. Wire 1 is 4 times longer and twice the diameter of wire 2. If they are both under the same load, compare (a) the stresses in the two wires and (b) the elongations of the two wires. Homework Equations stress...

Homework Statement The component shown in Fig 1 is made from a material with the following properties and is subjected to a compressive force of 5kN. Material Properties : Young’s Modulus of Elasticity – 200 GNm-2 Modulus of Rigidity – 90 GNm-2 Poisons ratio – 0.32 Calculate : (a) The stress...