Strain Definition and 462 Threads

Hi, I'm attaching a file which have the stress strain curves of same material at quasi static and high strain rates. See materials on page 1 and page 2. Both are same materials. The curve on page 1 is obtained at quasi static strain rate and the curve on page 2 is obtained at high...

Vibrations of a motor (40Hz) cause noise on the signal of a strain gauge that monitors load on a cantilever that measures periodic load changes at the rate of 1/minute. Design a filter that reduces the signal caused by the vibrations by 90%. I thought about a low pass filter that has a cut...

Homework Statement The strain hardening behavior of an annealed, low‐carbon steel is σ = 100,000ε0.2 If a bar of this material is initially cold worked 20%, followed by additional cold work of 30%, determine the probable yield strength of the final bar. Homework Equations σ=κεη...

Hello all. I am looking over various strain gauges as I need to purchase one for my project. However, I have never worked with them before, and I cannot seem to figure out how to know its accuracy (able to detect a certain change in pressure, for example changes of the scale of 1mmHg) ...

Homework Statement [See Attachment] Given: Thickness, load, G Find:γ and horizontal displacement. Homework Equations τ=γG Angle change should be the shear strain. The Attempt at a Solution I tried plugging 800 into tau and the given value of G to get γ, but that isn't...

If a wire is stretched to double of its length.What will be the strain of wire?I need to prove it mathematically that how it becomes 1.

A strain-gauge bridge is made up of four resistive elements, each element having an unstrained resistance equal to R, as shown in the diagram below. When a strain is applied to the bridge elements R2 and R4 increase in resistance by an amount ΔR, whereas R1 and R3 decrease by ΔR, where...

Homework Statement A Steel bolt having nominal Diameter of 20 mm and a pitch of 2.5 mm (Pitch is the distance from thread to thread in the axial direction), and an aliminium tube, 40 mm OD by 22 mm ID, act as a spacer for two plates. The distance between the two plates is 0.35 m. The nut...

Homework Statement There is a 104kg uniform log hung on two steel wires, A and B, both of radius 1.00mm. Initially, wire A was 2.70m long and 2.00mm shorter than wire B. The log is now horizontal. Note that the centre of gravity (com) is not necessarily centered between the wires and the...

I can't find the THEORETICAL definition of "strain optic coefficient" online. I googled and wiki'd enough. Can someone provide me with one, please?

Hello, is the strain defined as the absolute deformation to the initial ? i.e is it always positive ?? If Yes , then poission's ration is negative for compression of ordinary materials ?

I'm doing A-Level physics and I've been answering questions on Young's Modulus. I need to be able to explain why a long, thin wire is used when measuring the Young's Modulus of a material. I can give an explanation of why stress due to the wire being thinner is greater but I don't know why...

Homework Statement A plastic ball is inflated enough to produce tangential stresses. σX = σY = 2000Kpa The radial thickness of the material is 1.2mm brfore inflation. Find the thickness after inflation if the tensile modulus of elasticity is 3.4Gpa and the shear modulus is 1.4Gpa...

Hey everyone, I'm having some trouble with my material science homework. I really have no idea where to begin: Consider a piece of beam of 1 cm in length with one end fixed on a wall and the other end free (see illustration below). If you bend the beam by applying a force at the free end...

Homework Statement http://img683.imageshack.us/img683/7060/selection001l.png Homework Equations \epsilon^{pl} = \epsilon - \epsilon^{el} \epsilon^{pl} = \epsilon - \frac{\bar{\sigma}}{E} r = \frac{\epsilon_w}{\epsilon_t}The Attempt at a Solution I'm stuck trying to calculate \bar{\sigma}...

Dear all, I would like to know from you the solution about this problem (which is not a homework, but a topic of my Master thesis!): I need the strain energy density related to a circle of radius r0 centered in an arbitrary point of a square plate, under the boundary conditions described in...

Hi can someone please recommend a strain gauge to measure mass flow rate of a pneumatic conveying system. The full bridge circuit strain gauges are to be placed on a cylindrical cantilever beam with a length of roughly 160-170mm and a diameter of 36mm and made of iron. From what I have read...

Homework Statement I am working with an electronic bathroom scale and now have to find the relationship of the applied load which is mass in kg against the beam surface strain. The maximum load is assumed to be 75 kg. Homework Equations (M/I)(h/2)=Eε A picture of the beam has been...

Homework Statement Homework Equations \gamma_{max} = {\left|{\epsilon_1} - {\epsilon_2} \right|} The Attempt at a Solution I calculated the maximum shear strain to be 200 \mu. For the angle, I don't know exactly how to go about finding it. However, the solution says that the angle is...

We have 2D point coordinate before and after experiment(you can see the attachement), now we want to get the contour line of effective strain after deformation, is there any method or software to achieve it?

Question from one of my exams,I am lgoing crazy becaue this is against everything I understand. Please please please help me : http://imageshack.us/f/189/examh.jpg/ Basicaly,I need to found what the "0" degree shows me on elongation. As I look at the hole in the figure,I see the pressure...

Hey, everyone. I'm new here. This is a continuum mechanics question. If it's the wrong forum, please let me know, of course. The question is pretty simple, but since I haven't been able to find an answer, I'm looking for "crowd help". Green strain \mathbf{E} is usually defined implicitly by...

Homework Statement The question is: calculate the total amount of strain at fracture? How much of this is recoverable strain? Explain your answer Homework Equations strain = (change in length)/ (initial length) The Attempt at a Solution I'm not sure about my answer but i just...

Hello Folks, I'm after a little help here, I've been asked to calculate the maximum strain a beam is under at a certain deflection, for a part we are planning to get Rapid Prototyped It is a rectangular beam attached to a wall at one end I have the material data sheet for the material...

Homework Statement This is just a simple questions concerning the method of obtaining nominal stress and nominal strain. From various sources on the net they refer to nominal stress/strain as engineering strain therefore can I just use the simple equations for stress and strain? In this...

Hi All I am a mechanical engineering student and require to attach a full Wheatstone bridge to the underside of a cantilever beam, 103x27x5 mm LxWxH. Where would be the best location to mount the gauges?, also in which orientation should I mount them? All parallel to the length of the beam...

Imagine you have a cylindrical plug of plastic that you press fit into a hole. I need to determine the raidal pressure, radial stress, that the plug exerts on the wall of the cylinder. Here is what I have so far. Lateral Strain = (d_initial - d_final) / d_initial\ From what I...

Hello, I have problem with understanding the concept of energy of deformed body. As far as I know, Clapeyron's theorem states that elastic energy of deformed body is half the work done by external forces; this are surface and body forces which deform the body. Then, I wonder, where has...

Hi I'm studying strain analysis using Mohr's circle. I have some problem using a star rosette to construct the circle. My problem lies with trying to identify the points which indicate the planes the rosette act on. Besides that, what is meant by "strain rosette with gauge X (gauge X being...

Hello All, I am trying to learn the theory of elasticity from Landau's book and from the very beginning I've run into trouble. As I learned it, a (0,2) tensor T_ij obeys the transformation law T_hk=T(dx_i/dx_h)(dx_j/dx_k). But I do not see how a strain tensor can be transformed in such a...

Are these two things the same? I'm looking at bioabsorbable copolymers with similar properties to the human acetabular labrum, but I can only find tensile strength values for the copolymers and tensile stress at break for the labrum. I've looked at the definitions of each it sounds like the...

I have a very fundamental doubt regarding the stress strain graph for many materials..Normally we plot strain ~stress in the graph..but it seems that stress is the independent variable and strain is the dependent variable..but still why nowhere i have found the curve as stress~strain..can...

When plotting a stress against strain graph is this the right equation that fits the form y=mx+c? I got (F/A)=y(dL/L) where F is force A is area y is youngs modulus dL is change in length and L is original length. The Y is F/A. The m is y and x is dL/l (in y=mx) is this correct? Thank you

This is not really part of my homework but I still want to drive this equation. Continuity equation: p=density D/Dt=material derivative Grad: Gradient V=Velocity vector v=volume so; (1/p)(Dp/Dt)= -Grad.V and p=m/v then, (1/(m/v))(D(m/v)/Dt)= -Grad.V Following is what I can't seem to get...

Need help to calculate misfit strain? Homework Statement I would like to calculate the misfit strain on InP and InGaAs when InGaAs is grown on InP Homework Equations lattice constants for InP , a1= 5.8687 InGaAs a2=5.7455 ( with 25% In) The Attempt at a Solution I have...

Homework Statement I would like to calculate the misfit strain on InP and InGaAs when InGaAs is grown on InP Homework Equations lattice constants for InP , a1= 5.8687 InGaAs a2=5.7455 ( with 25% In) The Attempt at a Solution I have calculated the lattice mismatch ratio as...

Design a circuit that uses a stain gauge to create a voltage related to the strain experienced by the gauge. The strain gauge should remain electrically isolated from the ground. The DC common mode voltage should be minimized. Only stain-related signal to be measured does not have any...

Howdy ya'll, a relatively simple question, A circular bar 20mm in diameter and 1m long is subjected to an axial load of 50kN. Determine: (i) The normal stress. (ii) The normal strain. (iii) The elongation. Assume the material is steel with an Elastic Modulus of 200GPa. ok so i...

Hi Guys, So I am biting off more than I can chew with my latest project.. and looking for help. I am going to fabricate a kit car chassis, The suggested material is 1' x 1' steel box section but why? Could anybody help by suggesting the kind of calculations I would have to research...

using excel 2007, can the construction to determine the proof stress of a material not be done manually? if so, how?

Very simply put. Is it possible to determine bending stress in a beam without knowing the young's modulus of the material used? All equations I've seen seem to include in some form an E value ( young's modulus), which is used in conjunction with a stress value to evaluate the strain.

I have the folowing continuum mechanics problem which I can't solve: The unit elongations at a certain point on the surface of a body are measured experimentally by means of strain gages that are arranged at 60° in the direction of 0°, 60° and 120°. Coordinate system is rectangular Cartesian...

I have the folowing continuum mechanics problem which I can't solve: The unit elongations at a certain point on the surface of a body are measured experimentally by means of strain gages that are arranged at 60° in the direction of 0°, 60° and 120°. Coordinate system is rectangular Cartesian...

Currently I am studying the mechanical properties of artery tissue, and was tasked with determining if the tissue fails due to shear stress or shear strain. I have always worked under the assumption that they go hand in hand with each other, but the nature of this question obviously suggests...

Hey physics forums people, this is my first post ever and I am not sure if this is the right sub forum, but w.e, let's try this out anyways Homework Statement K so the problem is I've got a weight hanging on the shear centre of a cantilever and there are strain gauges all over it It is an L...

In lab for our final project, we used a Wide Range Strain Indicator connected to strain gages on a part we machined to function as a scale. The Indicator device was much like this one: http://www.datasheetcatalog.org/datasheet/vishay/3800.pdf What units would the numbers be that we're...

This is a homework problem and I thought about putting it in the homework section bu since its very materials science specific I decided to put it here: For a transversely isotropic material, the “plane strain bulk modulus”, K23, is an engineering constant that is defined by the stress...

Hi, I have a solid cylinder to which I have strain gauges attached to measure axial and circumferential strains. My goal is to relate the circumferential strain to radial strain and then to calculate possion's ratio. Every time I try to work out the geometry of the problem I end up saying...

Homework Statement Hello, I've been given a question: The ultimate strength of a round steel rod is 560MPa. If a factor of safety is 6 is required, what is the maximum permissible load for the rod if it has a diameter of 6.9cm? If anyone can explain how to set up this...

do strain gauges need calibration