What is Beam: Definition and 1000 Discussions

An I-beam, also known as H-beam (for universal column, UC), w-beam (for "wide flange"), universal beam (UB), rolled steel joist (RSJ), or double-T (especially in Polish, Bulgarian, Spanish, Italian and German), is a beam with an I or H-shaped cross-section. The horizontal elements of the I are flanges, and the vertical element is the "web". I-beams are usually made of structural steel and are used in construction and civil engineering.
The web resists shear forces, while the flanges resist most of the bending moment experienced by the beam. The Euler–Bernoulli beam equation shows that the I-shaped section is a very efficient form for carrying both bending and shear loads in the plane of the web. On the other hand, the cross-section has a reduced capacity in the transverse direction, and is also inefficient in carrying torsion, for which hollow structural sections are often preferred.

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  1. H

    Polarization of white light beam

    I want to find out that what happens if we polarize a white light which has all of the wavelenghts of 400-700 (nm).Does it divide into colors?What happens to it?
  2. B

    Natural Vibration of Beam - Algebraic Query

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  3. B

    Finding Net Torque on a Beam: Calculating Torque about Different Axes

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  4. B

    Natural Vibration of Beam - PDE

    I am just wondering the author is doing in this calculation step. Given ##\displaystyle \rho A \frac {\partial^2 w}{\partial x^2} - \rho I \frac{\partial^4 w}{\partial t^2 \partial x^2} +\frac {\partial^2 }{\partial x^2}EI \frac {\partial^2 w}{\partial x^2}=q(x,t)## where ##w(x,t)=W(x)e^{-i...
  5. C

    Pion production with an electron beam

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  6. B

    Statically indeterminate beam (fixed ends) and the moments at the supports

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  7. S

    Length & Bending Stress: How Does Beam Length Impact Stresses?

    if you have a beam or something, anchored at one end and apply a moment at the other end, then the bending stress is given by M*y / I, where I is the moment of inertia of the beam. what affect does the length of the beam (i.e. the distance between the anchor and the end of the beam, where the...
  8. B

    Exploring Beam Deflection: Area Moment, Moment of Inertia & Center of Gravity

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  9. B

    Kinematics of Euler Bernoulli and Timoshenko Beam Elements

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  10. S

    I Beam Trolley Bearing Type

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  11. N

    Find the Shear and Moment on the Beam

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  12. Telemachus

    Stern-Gerlach, polarized atom beam.

    Homework Statement In a Stern-Gerlach device, an atom beam with angular impulse J, travels through a magnetic field applied normally to the trajectory. The beam is separated in 2j+1 beams in general. Find the relative intensities for these beams if J=1 and if the beam is polarized with jθ=1 in...
  13. C

    How to work out the mean shear stress I section beam

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  14. M

    Moment of Inertia of a hollow beam inside a rubber shell

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  15. M

    Calculation of Bending Moments and beam deflection

    Homework Statement The picture of the beam below has a module of rigidity EI, determine the reactions at the supports and the equation of the deflection curve of the left half of the beam Homework Equations v*EI=((Ma*x2)/2)+((Ra*x3)/6) Ʃ of Forces in Y direction = Ra+Rb=0 Ʃ Moments...
  16. R

    Hinged beam suspended at an angle

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  17. S

    Fixed Ended Beam applied to couple moment

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  18. M

    Multi-Section Beam Bending Calculations

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  19. B

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  20. Z

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  21. B

    Moments of deflection/ curvature of radius of a supported beam

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  22. B

    Euler Bernoulli Beam 4th order ODE -Balance of Units

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  23. T

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  24. 1

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  25. S

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  26. D

    MHB Vibrating beam concept question

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  27. M

    Kinetic Energy of Electron Beam.

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  28. C

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  29. C

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    Been doing some physics problems from my mechanics class. This is the first time I've attempted a problem like this and am not so confident with solving it, I could be correct and just being paranoid but I just have a feeling I've made a mistake somewhere, would appreciate if someone who is...
  30. M

    Obtaining the Green Function for Euler Beam with Specific Boundary Conditions

    Hello there, I would like to obtain the Green function for the operator F, F [u(x)] = u '''', and the boundary conditions u(0) = u'(0) = u (1) = u' (1) = 0. I am looking for a function G ( x, s ) such that G'''' (x,s) = delta (x-s) (the apecis referring to differentiation w.r.t. x, and...
  31. S

    Cantilever Beam Failure as a function of Force Applied to Free End

    Hello, First post, go easy. Trying to do some basic calculations on how to find when a steel cantilever beam will yield when a load is applied to the free end of the beam. I have attached my best MS Paint diagram of the problem. Assume the left end is clamped and essentially a fixed end...
  32. D

    A cantilever beam, find the tension forces

    Homework Statement http://i.imgur.com/5p9UF.jpg The Attempt at a Solution http://i.imgur.com/LZtRh.jpg and this is what was tried to do. But apparently T2 is complete off, any ideas? Or there is some other way to calculate this? Or perhaps someone can point me to better book other than...
  33. P

    Why is the second cross section preferred for designing a beam?

    Consider the cross section of two beams of same material as shown in the file attached. The area moment of inertia I about the central axis is equal for both the c/s. I have calculated it. Can somebody explain why the second c/s (2 in the figure ) is preferred for the design?
  34. R

    Maths solution for partially restrained cantilever beam

    Hello Can somebody guide me to a mathematical solution for a cantilver beam which is totally restrained on only 2/3 of its depth. Thanks in advance
  35. Telemachus

    Particle beam without spin into a magnetic field

    Hi there. I have to solve this problem. The statement says as follows: A particle beam with l=1, without spin and with momentum p is incident on the plane x= 0. In the region x<0 the particles move freely and for x>0 are under the action of a constant magnetic field H in the z direction V(x) =...
  36. H

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    Hi, Please do not shout at me if you find this query posted on another thread; I am spreading my net wide. I am investigating the overhang beam pressure distribution when part of the beam is resting on an elastic foundation. We are all aware of the assumption that when a moment is reacted...
  37. karush

    MHB Max Beam Deflection: Find $x$ Value for $D$

    The deflection D of a beam of length L is $D=2x^4-5Lx^3+3L^2 x^2$ where $x$ is the distance from on end of the beam. Find the value of $x$ that yields the maximum deflection. this is from a unit on inflection points so assume this is $\frac{d^2}{dx^2}$ and also looks like an implicit...
  38. L

    Torque of man on a beam trying to paint his house

    A man of mass mm = 95 kg decides to paint his house. To do this, he builds a platform using a uniform beam with a mass of mb = 100 kg and a length of L = 7 meters. The beam is supported by two sawhorses, as shown in the diagram above. 1) If the man stands over the support at point B...
  39. H

    Find height of ball under water beam

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  40. L

    Tension in the hawsers holding a beam

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  41. E

    Moment of a Distributed Load on Beam, Scanned work and Diagram.

    Homework Statement Determine the forces of reaction.Homework Equations SUM of Y forces=0 SUM OF FORCES ABOUT POINT B = 0 The Attempt at a Solution My attempt is in the link, I scanned the diagram along with my work. Thanks for the feedback, appreciated. http://imgur.com/i3cB2 <----- Link
  42. A

    Vibrating uprigt cantilever beam

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  43. A

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    If I start out with a flat beam of length a and then I fix one side and then bend the other side up to form an arc with height h, is that enough information to determine the radius of curvature of the bent beam? If so, how would I do it? Thanks...
  44. V

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    Homework Statement A beam (note: part of a truss, I chose to use the beam in the truss with the most force and length for my calculations, which I assume is the correct thing to do) of length 6m with a force of 9N is being constructed out of a material with a Young's Modulus of E = 70 \times...
  45. T

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    Hello guys, I'm not sure this is the right place to ask the question, but I hope someone would have experience with beam splitters cubes. If I want to split a laser beam over more than one level with more than one beam splitter cube, so the first beam splitter splits to two beams with 50%...
  46. E

    Tapered cantilever beam deflection and stress distribution

    Homework Statement A positive moment of 12000Nmm at the tip applied as two equal and opposite point loads of 1000N in the x direction at C and D. The beam is fully fixed along AB. Young's modulus E = 200*(10^3) MPa and the poisson's ratio = 0.3. Geometric Properties: Width, b=10mm...
  47. D

    What is the required force to achieve constant radius beam bending?

    Hi All, I need to calculate how much force is required to bend a beam to a constant radius. The beam will be simply supported on both ends and the force will be applied much like a 3 point bend but with a curved face instead of a single point. For most of my application, the beams are...
  48. J

    Gaussian Beam Width and Refractive Index

    Homework Statement I know that in free space, the width of a Gaussian beam can be written as W=W_0\sqrt{1+(\frac{z}{z_0})^{2}}. However, I was wondering if it was possible to express this width as a function of refractive index instead (since I don't believe a Gaussian beam originating in say...
  49. R

    Axial traction of a beam on support

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  50. Saladsamurai

    Short Beam Bending: Roark's Formulas For Stress and Strain

    Is anyone familiar with the Roark's text that can clarify some terms for me? I am trying to clarify what Roark is referring to in the above mentioned text in the section on short beams (in the 5th edition 7.10 and in the 7th edition 8.10). Throughout the text, he uses the terms "span" and...
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