Stress Definition and 1000 Threads

A concrete column having a modulus of elasticity of 20GN/m2 is reinforced by two steel bars of 25mm diameter having modulus of 200GN/m2. Calculate the dimensions of a square section strut if the stress in the concrete is not to exceed 7MN/m2 and the load is to be 400KN. σ in conctete not...

A compound bar is made using stainless steel tube with an aluminium alloy bar positioned concentrically inside it, and rigidly fixed at each end. The cross sectional area of the tube is 400mm^2 and the cross sectional area of the bar is 300mm^2. The combination is in tension and limiting stress...

what is shear stress?what is its direction?

Hello, I am having confusion when calculating the first moment of area, Q, to solve for the shearing stress at point a in 13.9, I use the area which is above the point, but for 13.28 its to the right of the point. It seems they are both subjected to a vertical shear, so I don't think that has...

A solid shaft 100mm diameter which transmits 75kw at 150 rev/min. the question is asking me to find the max shear stress and angle of twist per metre of the shaft length. G=80GN/m^2 I was under the impression to find the angle of twist you needed the length in the first place. None of...

Homework Statement An element is taken from the wall end of the cantilever beam that is loaded as per the diagram. What are the stress components of the element, taken at x=0, y=h/2, z=0 Homework Equations σ=My/IThe Attempt at a Solution So from the shear moment diagram, the moment and shear...

A light alloy bar is observed to increase in length by .35% when subjected to a tenstile stress of 280MN/m^2. Calculate youngs modulus for the material. σ=280MN/M^2 x=.35% ε=? E=? L=? I have too many unknowns where do I start?

Hi guys, I have been wondering if its possible to alter equilibrium concentrations without adding stress to the system? Thanks, Larry

We solved a problem today in class calculating stress in a compound tube. I haven't posted the full question because I don't think I need to. There are two areas that I am not sure how we found them, EX 1: -60*10^6 how does 10^-6 and 10^9 become 10^6 and Ex2: 6.7*10^-5 and here how...

Homework Statement DIAGRAM ATTACHED AT BOTTOM Q. The following statements are true for an element in plane stress state. (this is 2D) (1) one of the principle stresses is 40Mpa; (2) σx= -2τxy; (the algebraic values) (3) in x'oy' with θ=30°, the two normal stresses σx'=σy' Determine...

Should it be added to the Cauchy stress to calculate a "total stress", or it doesn't have such a physical interpretation as a surface force(EM field force is usually considered more of a "body force")? Certainly when the MST was first derived before aether theories were made superfluous by...

I am familiar with the formula for energy density: \frac{1}{2} * \frac{Force*Extension}{Area*length} and also the formula for elastic potential energy: \frac{1}{2} * Force*Extension. I noticed that there is a 1/2 in both formulas because we are concerned with the average force in each case...

Could anyone explain the method of finding the circumferencial and longitudinal stress for thick cylinders?

Hello all, I am confused on how to calculate the maximum bending stress in an I-beam. I found the maximum deflection in each beam where the load is placed at the center of the span. I also know all the cross-sectional dimensions of the I-beam. Is it now possible to calculate it? Thanks

Homework Statement 1. Take dimensions of the beam (B, D, web and flange thickness, L) – T- cross section 2. Take the beam span geometry and material properties from the instrument 3. Ensure the beam and load cell are properly aligned and apply a positive (downward) preload to the beam of...

Homework Statement A tunnel of length L = 151 m, height H = 7.7 m high, and width 6.2 m (with a flat roof) is to be constructed at distance d = 60 m beneath the ground. The tunnel roof is to be supported entirely by square steel columns, each with a cross-sectional area of 960 cm2. The mass of...

Hi all, This is a question regarding stress and strain. Can someone please explain the concepts of stress and strain in atomic level? My understanding is as follows.Let us consider a metal bar or rod that is subjected to tension.The load applied to the bar will be try to elongate the...

Hi all, This is a question regarding stress and strain. Can someone please explain the concepts of stress and strain in atomic level? My understanding is as follows.Let us consider a metal bar or rod that is subjected to tension.The load applied to the bar will be try to elongate the...

1. The scenario is the same as this (with a circular cross section): http://upload.wikimedia.org/wikipedia/commons/c/cf/Poutre_flexion_deviee.svg 2. Do I simply calculate the stresses from each bending moment and add them together? Or take the resultant vector and calculate...

Homework Statement i am study for a physics test and i think my physics teacher gave me the wrong equation for shear stress Homework Equations she gave me F=Δx/l *A The Attempt at a Solution

Hi there, I'm trying to find a solution to a problem that I thought was straight forward, but am now struggling with. I've got a shaft with a fixed end set up, where there is a small diameter fixed and then it steps up to a larger diameter which is having a torque applied to it. I'm...

Hi, from what I know, the crushing force for sugar cane is somewhat similar to pine wood which is about 40 MPA. But since there's water content in it, I need to readjust the yield stress for to crush the sugarcane. I've tried googling it but couldn't find much useful information. Anyone knows...

Homework Statement A plate with a hole in the centre is loaded in tension It has a height of 86mm (W), a thickness of 12 mm, a hole diameter of 33mm and a yield stress of 346MPa. The tensile load is 117kN. A) Determine the stress on the top edge of the hole B)Determine the stress on the top...

Hello, I am having difficulty solving for the Area and wondering if this is correct.

Hello, I am wondering, is the area A in the equation meant to be the area of the empty space in the shaft, going all the way to the half way point of the structure (meaning, the area of the space included in the dotted lines in the diagram on my attempt?

Homework Statement so the question I got from my teacher is: A cast iron pipe of external diameter 60mm and 10 mm thickness and 5 m long is supported at its ends. The pipe carries a point load of 100N at its centre. Calculate the maximun flexural stress induced? Homework Equations I...

Homework Statement (a) By using either the vector algebra or polygon methods for finding a resultant, determine the magnitude of F that will cause the net effect of the three forces to act vertically. (b) For that value of F, determine the stress in the bolt’s 1-cm diameter straight shank...

Homework Statement Show that a stress function of the form \phi(r,\theta) = f(r)\cos(2\theta), where f(r) is a function of r only, satisfies the biharmonic equation and hence an admissible Airy stress function. Homework Equations g \equiv \nabla^2 \phi = \frac{\partial^2 \phi}{\partial...

I can't go into detail right know - but the thing is: in order to make a real antimatter engine one would need to make a loop of SCs wire r = 70 m, where r(wire) is approx. 20 cm. I need to generate about 10 T in the center of the field, that is 70 m from the nearest wire. How much mechanical...

Hello everybody, Here is a problem I have. QUESTION: The main span of a bridge has a length of 473 m. On each end there are the expansion joints like the one on the photo below. One day the city changed from -4 to +15 degrees between 6 in the morning and 2 in the afternoon. At 6 in...

Greetings all, I have been trying to find a method of calculating the yield stress for a material when only given; -The loading type (Two bars soldered together in tension) -The dimensions of the shaft and solder (ie thickness of solder, length, cross sectional area) -The Ultimate...

Hello, I am not sure what the first indice in the cauchy stress tensor indicates For example, σ_xy means that the stress in the y direction, but does x mean the cross sectional area is normal to the x direction?

Hello, I am looking at my lecture notes PDF, and I am having trouble seeing the geometry how A_θ is A_0/cos θ. I can understand how the force acting on that cross section is Pcosθ, just not the part about the area for which F is acting. I think F is normal to the plane, so the cross section...

Hi, I have a problem which you guys probably could help me solve or at least advise how to approach. I am building a mechanical system that consists of 2 steel rods acting as rails and a platform that travels along. I need to find radius of curvature of a steel rod under stress to see by...

Hi everyone, I was looking up Mohr's circle on planar stress and stress/strain relation and all that and I read a context on principal stress. It said that if there is both normal (tensile) stress and shear stress in a given area, then the principal stress at that location is greater than...

Hi everyone, I wanted to know the stress concentration factor (Kt) for a cantilever beam with a fillet at the root with a point load applied at the end. Can I get the stress concentration factor if this beam is a 3D beam (thickness is comparable to length)? I had a look at Peterson's SCF...

Homework Statement The stress function \phi(x,y) = \frac{q}{4c^2}\left(c^2xy - cxy^2 - xy^3 + cLy^2 + Ly^3\right) is proposed as giving the solution for a cantilever (0 = x < L, -c \leq y \leq c) loaded by uniform shear along the edge y = +c, and stress/traction free along the edge y = -c and...

Can someone explain to me how the Prandtl stress function is derived? The book only briefly describes how the Airy stress function is derived.

Homework Statement Piano wire weighs 77kN/m^3 and breaks at a stress of 3000MPa. Calculate the length of piano wire that can be lowered down a very deep mine before it breaks. Homework Equations stress = force/area The Attempt at a Solution Piano wire = 77 000N/m^3 stress = 3000...

I studied that Stress is defined as Force per unit area. Force here referred to internal force between the particles in the materials per unit area. am i right? Is pressure a kind of stress? (Internal force per unit volume) for fluids but i have studied that pressure is external force per...

Dear All, I just have a single element, I need to apply a plane stress condition as in the attached image. For the boundary conditions; • I have constrained the nodes 1 and 2 in the horizontal (x) direction • I have constrained the nodes 1 and 3 in the vertical (Y) direction • I have...

Homework Statement Consider a fluid between two plates. One on the bottom which is stationary, and one at the top which is moving at constant velocity V. The plates are separated by distance h. Does shear stress change as you move further from the moving plate? Homework Equations the...

Hi guys, I would like to know if the answer given to this thread is correct https://www.physicsforums.com/showthread.php?t=457405 I got the same doubt, is the expression for the tensor given in cartesian coordinates or is it general to any orthogonal coordinate system? Thanks in advance

Hi, I have done hoop stress calculation on thin walled pipes. But, will gear tooth also go under hoop stress when loaded? Can somebody explain the procedure to calculate that pl.? Thanks.

Homework Statement It's a relatively simple problem I'm sure, but I'm a bit confused on how exactly to go about it: There are three parallel plates with water (viscosity of 0.8807 cp @ 30°C) between plates 1 and 2 (plate order of 1 on bottom, 2 in middle, 3 on top), and toluene (viscosity...

I'm wondering if there is a calculation that can be used to work out the maximum stress on an object upon impact. Say for example an object strikes a rigid wall, how would one go about calculating the stress on that object?

Hi all, I have a very basic question regarding the topic of stress.While deriving the equations of equilibrium for a plane element,there is a concept called incremental stress.That is,if stress in the x direction for one face is σx the stress in the opposite face is σx + (δσx/δx)*dx. Where the...

During fight-or-flight situations, alpha 2 receptors ( which are inhibitory receptors ) of the pancreatic beta cells are stimulated, and as a result there's decreased insulin production. While it benefits the body by producing increased blood sugar level, I don't understand why Insulin doesn't...

How do you calculate Stress of a curved beam?? Hi there, I'm new here so I got a project to make a windscreen on solidworks and analysis using FEA no problem :) However I'm also asked to analysis stress on the windscreen experienced by the air resistance manually, I have worked out the air...

Hi all, I have started with my understanding of pressure vessels and i have some queries on the topic. 1) I understand the part of axial stresses.When a cylinder capped at both ends is subjected to internal pressure,it tends to increase the length of the shell,and therefore a resistance is...