What is Shear: Definition and 621 Discussions

Shear stress, often denoted by τ (Greek: tau), is the component of stress coplanar with a material cross section. It arises from the shear force, the component of force vector parallel to the material cross section. Normal stress, on the other hand, arises from the force vector component perpendicular to the material cross section on which it acts.

View More On Wikipedia.org
Recent contents Top users
  1. C

    Sign convention of shear force and moment on beam

    Homework Statement I don't understand why the sign of moment of beam at left (clockwise) and moment at the right of beam (anticlockwise) are considered as positive... Why we can't assume the clockwise moment as positive and anticlockwise moment as negative? Homework EquationsThe Attempt at a...
  2. C

    Sign convention of shear force and bending moment

    Homework Statement http://nptel.ac.in/courses/112107146/22[/B] in the notes, the author define upward shear force as positive (LHS) , he take downward shear force as positive as positive (RHS)? Homework EquationsThe Attempt at a Solution why the author didnt fix downward shear force as...
  3. C

    Is Shear Force Always Maximum When Moment is Zero?

    Homework Statement in the book , i was told that when the shear force is 0 , moment is maximum . However , in this question , i found that when the shear foce is 0 , the moment is also 0 . I'm wondering is the ststemnet true ? Homework EquationsThe Attempt at a Solution
  4. C

    Angle of shear stress vs normal stress

    Homework Statement why the angle of shear stress ( θs) is given by θp - 45 ?? Homework EquationsThe Attempt at a Solution the difference in angle of shear stress and normal stress is90 degree , am i right? why it's negative 45 degree? is it wrong?
  5. P

    What is the shear flow equation for the lower horizontal bar in a hat section?

    Homework Statement I've a problem with defining x function for the lower horizontal bar on the left hand side. Is it shear flow for this part = Vx/Iy * 3 * s^2 * 0.5 (after integration) ? Or should I take whole x part on which is acting force Vx? Homework EquationsThe Attempt at a Solution
  6. F

    Shear stress and normal stress

    Homework Statement why the shear stress is maximum at the center ? while the normal stress is maximum at the boundary ? Homework EquationsThe Attempt at a Solution why shouldn't the shear stresss maximum at the boundary ? this is because shear stress is to pull the 2 surface apart [/B]
  7. H

    Moments and shear force diagram

    Hi Can someone please help me with this problem: A beam is 16m long and rests on two supports, 10m part. the right support is 4m from the right-hand end. The beam carries a uniformly distributed load of 408 kg/m between the two supports and concentrated loads of 2kN at the left end, 0,153 tons...
  8. H

    Shear stress on surface of a bar

    Homework Statement I want to understand why in noncicular members in torsion book tells me that surface of a member is free and so no shearing stresses there. This is from wikipedia for shafts: Note that the highest shear stress occurs on the surface of the shaft, where the radius is...
  9. R

    How Do You Calculate Shear Strain in a Crystal?

    I don't know how to solve this kind of problem: Given a crystal and its volume V. This Crystal is subjected to a shear stress making a slip plane (h k l ) in a slip direction [h k l]. Given also the lattice parameter a and slip plane spacing L, and the edge dislocation a/2 that passed halfway...
  10. I

    Calculating the maximum shear stress in a shaft

    Homework Statement Homework Equations Torque = Force x Distance Shear stress = Force/Area 3. The Attempt at a Solution I know how to do this question as I've seen the mark scheme. However, initially I did it wrong. What I did was as follows: Torque = Force x Distance therefore...
  11. R

    Why does shear force direction change in the middle of a beam?

    I don't get this shear force distribution stuff. In my drawing A is sort of a free body diagram. Load W is dead center of a beam, and of course this force is supported at either end by two reaction forces.with a value of W/2. B is a shear force diagram. For points < L/2, shear force is...
  12. J

    Single shear element in stress tensor: Finding Von Mises

    When finding the Von Mises of given a stress tensor who's only element is a single shear component (τ): \begin{bmatrix} 0 & τ & 0\\ τ & 0 & 0\\ 0 & 0 & 0 \end{bmatrix} the result is simply √3×τ. Is the Von Mises criterion not valid when considering a single component as in this example? I...
  13. W

    Shear Stress on sleeve with grooves

    1. There is a valve body in which there is a butterfly plate. A shaft goes through the butterfly plate allowing it to open and close. A sleeve is inserted into the I.D. of the butterfly plate that the shaft goes through. The I.D. of the hole (butterfly plate) that the sleeve is inserted is is...
  14. Jonski

    Different values of shear modulus

    After completing two experiments to find the shear modulus of a beam, I found two very different results. For test 1, we twisted the beam slowly at very small angles (0.005 - 0.03 rad), only in its elastic form. The torque was found using a torsiometer . In test two a replica of the beam was...
  15. sharmax

    A Raychaudhuri Shear Equation in Different Sign Conventions

    Hi, I derived Raychaudhuri Equations in both (- + + +) and (+ - - -) sign conventions from metric. In Robert Wald and Sean Carroll books, (- + + +) sign convention and I derived correctly in that Sign Convention as given in the books. In the other convention, I am having one sign difference in...
  16. P

    Bending shear stress distribution

    I modeled a simple cantilever rectangular beam in Patran of (L,W,H = 100, 6, 4) with Hexa8 elements and applied a vertical shear load (upwards) of some magnitude at the free end. Ran in Nastran and plotted the vertical shear stress distribution on a cross-section in middle of length (in order...
  17. zaakir

    Calculating Shear Force and Bending Moment

    hi all Basically I need to find the shear force and bending moment of a beam using octave. The length of the beam as well as forces and their distances are given. However the SF and BM must be calculated at every o.ooo5m. The forces can be Point Loads or Uniform Distributed Loads and there can...
  18. OKaraali

    Max Shear Stress in Thin Cylinder: Issues & Applied Pressure

    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.
  19. M

    What is the reasoning behind the different forms of F in bolted joint equations?

    I am having trouble understanding the F used in these equations. Is it supposed to be the force F shown on the left, or is it F/2 or F/4?
  20. Z

    Solving Oneaxial Shear Test: Find Shear Force

    I´m really struggling to find the shear force here. 1. Homework Statement Hight h of a specimen = 100mm and diameter is 54mm. Max force F=144,6 N and deformation is δ=5mm Homework Equations I have to find ε=δ/h Area of specimen before deformation=54mm*100mm=5400mm σz =(F(1-ε))/A Shear force =...
  21. F

    Shear Stress Formula: Calculating Tau Correctly

    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 , so i didnt...
  22. B

    Finding out Shear rate of a bent pipe which has different bend radius values

    which has different radiuses at both end. Its actually two pipes merging after the entrance going straight and somewhere close to middle of the pipe it's bent 90°. So for simple pipes it's =4*Q π*r^3 But what for the pipe I...
  23. M

    Schmid Tensor / Resolved Shear Stress question

    Homework Statement Calculate the magnitude of the resolved shear stress on the ## (112)## plane in the ##[11\bar{1}] ##direction in a bcc crystal. Homework Equations Tried to use: ## t^{\alpha} = \frac{1}{2} \sigma_{ij} (m_{i} n_{j} + m_{i} n_{j}) ## where m is the direction and n is the...
  24. C

    Maximum bending Moment and Maximum Shear Stress Question

    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...
  25. F

    Shear stress for contracting pipe

    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...
  26. H

    Calculating Shear Stress: Solving for μ = ρv in 8-41 Equation

    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 ?
  27. G

    Understanding the Calculation for Shear Stress of Water

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

    Welding shear and normal stress calculations

    Hello, Does anybody know how to compute shear and normal stresses which take place due to applied load? My case is a simply supported beam (120x120x6.5 length: 4.2m) reinforced by a plate (20x120 length: 2m). Plate is welded on a top of a beam and external force (F=15 kN) is applied to the...
  29. S

    Shear Stress in Beams - Full Working, getting wrong

    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...
  30. D

    Producing a shearing force diagram and bending moment curve

    Homework Statement A box shaped vessel, of ##4## compartments and ##80m## lenght, light displacement of ##800## tonnes loads ##200## tonnes in the first compartment and ##200## tonnes in the last compartment. Produce the shearing force diagram and bending moment curve. Homework Equations 3...
  31. H

    Calculate shear strength A36 plate

    I'm trying to build a tank to hold diesel fuel, it will be on skids to lift with a fork lift but I also want to extend the the sides to provide a way to raise the tank from two attachment points on each side. The sides will be 1/4 A36 steel plate and the rest of the tank will be 10 gauge...
  32. loststudent123

    Designing Shafts to Withstand Shear Stress

    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]...
  33. loststudent123

    Find Shear Stress in Shaft Design | Modulus of Rigidity 80kN/mm2

    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...
  34. D

    Shear force and bending moment diagrams question

    Homework Statement In the image uploaded below, a boxed shaped object is shown. It is floating in water so the forces that act on it are buoyancy and gravity. The first and the last compartments are filled with evenly distributed weight. The middle 2 compartments are empty. Specifics are...
  35. S

    Calculating Shear Stress for Cylinder w/Grooves & Dogs

    Hi there I've got a task where i need to use manual calculations with this setup (see attach.) there is a cylinder with two internal grooves (yellow part). 5 Dogs are equally spaced (72deg.) inside that cylinder. They are being pushed by the Force against the grooves in the cylinder. What...
  36. P

    Shear stress in a thin profile

    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...
  37. R

    Bending and Shear Forces Homework Solutions

    Homework Statement Homework EquationsThe Attempt at a Solution
  38. M

    What is the shear modulus of viton material?

    i am new to rubber components , now i am developing a bladder for pulsation dampener, so for that i need to check the spring rate or elasticity of viton material and to determine the thickness for the bladder, I am struggling a lot to find the shear modulus of rubber, if have this valve i have...
  39. S

    What determines the sign/direction of shear stress?

    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?
  40. V

    Fluid Shear Paradox: Is There Shear?

    A fluid with forced vortex flow and constant angular velocity is given. Newton's shearing says there must be strain due to differential linear velocity. The problem is, the difference of linear velocity is only visible to the external observer, the fluid particles themselves do not observe...
  41. shott92

    Bending force or shear force what's the difference?

    Hi today I was watching a demonstration of using explosives in demolition and emergency rescue and they did one where they wrapped explosive cord around a steel I beam and cut it in half then said this was a shearing force which sounded right to me but then they took a concrete post similar...
  42. G

    How Do You Calculate Shear Stress in a Coronary Artery?

    Homework Statement Blood supply to the heart occurs through coronary arteries. Consider one of the arteries to be 2.5 mm in diameter and 3 cm in length. The average velocity of blood flow through that artery is 1.5 cm/s. Assuming the density of blood to be 1.056 g/cc and viscosity to be 3 cP...
  43. J

    Will my steel ejection mold bolts shear under sideways load?

    hello. I have a ejection mold (steel) which has a bridge like mount which locates the handling eye bolts outward around hydraulic cylinders. I need to make sure the bolts in the bridge will not shear due to the sideways load when the mold is lifted or flipped 90degrees. Here is the known...
  44. B

    Solving Shear Strain Problem: Find Vertical Displacement

    Homework Statement The support consists of three rigid plates, which are connected together using two symmetrically placed rubber pads. If a vertical force of 5 N is applied to plate A, determine the approximate vertical displacement of this plate due to shear strains in the rubber. Each pad...
  45. E

    Shear Forces on Dams: Struggling Amateur Needs Help

    Im struggeling with understanding this task. Yeah I'm an amateur.. My English is not that good as well. My main problem is understanding where the share forces act on this dam, if its through the centre of pressure, or if its at the bottom of the dam. Now I have calculated the share forces...
  46. nick miller

    Finding the average shear stress

    Homework Statement Find the shear stress alone the cylindrical area of the plate, and the average shear stress in the bolt head along the cylindrical area. the plate is 30 mm thick bolt head is 8 mm thick bolt head diameter is 18mm bolt shank diameter is 7 mm shank has 8 kn along it...
  47. P

    Visualization of Fiber orientation in simple shear flow

    I need help on where i can find the numerical study and a MATLAB code on how to visualize the distribution function and orientation tensor of fibers in simple shear flow for different closures as it is shown in Fig.1 and Fig.2 of the following paper...
  48. A

    Find λ for Non-Uniform Scale & Shear Transformation

    Homework Statement Find the two numerical values of λ such that \left(\begin{array}{cc}4&3\\1&2\end{array}\right) \left(\begin{array}{cc}u\\1\end{array}\right) =λ \left(\begin{array}{cc}u\\1\end{array}\right) Hence or otherwise find the equations of the two lines through the origin which...
  49. P

    Bending moment and Shear Force

    Do bending moment and shear forces are dependable on a beam's cross sectional area?
  50. MexChemE

    Transport phenomena -- Direction of shear stress

    Greetings, PF! I have some questions regarding the problem I attached below. It is some sort of Couette flow variation. It's not homework, I'm just learning the basics of TP on my own. I fully solved the problem with the Navier-Stokes and continuity equations, using some assumptions in order to...
Back
Top