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. R

    Tapered, arched beam stiff mass matrices ?

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  2. M

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  3. N

    How Can You Effectively Widen a Laser Beam for Experiments?

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  4. V

    What Metal Best Emits Infrared Light for Camera Detection?

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  5. S

    Energy/particle number uncertainty in a laser beam

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  6. A

    Deflection vs. Bending in a Beam

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  7. S

    Second moments of area of a simply supported regular I beam

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  8. Z

    Boundary Condition for deflection of Beam

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  9. H

    Torque/moment of beam in equilibrium

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  10. M

    Gaussian Beam in a Symmetric Confocal Resonator.

    λHomework Statement A symmetric confocal resonator with mirror spacing d =16 cm, mirror reflectances 0.995, and n = 1 is used in a laser operating at λ[o] = 1 μm. (a) Find the radii of curvature of the mirrors. (b) Find the waist of the (0,0) (Gaussian) mode. (c) Sketch the intensity...
  11. M

    Elliptical partially polarized beam and its intensity

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  12. R

    Law of physics for beam sizes

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  13. B

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  14. B

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  15. V

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  16. P

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  17. M

    Inelastic collision of ball with rotating beam (juggling robot)

    Homework Statement I'm trying to build a "juggling" robot but I'm getting stuck on the dynamics of catching. The robot follows the dynamics and terminology of a similar one presented in the attached paper (equation 1). Basically, there is a circular ball flying through the air which lands (and...
  18. V

    Spring stiffness calculation - Curved beam

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  19. StevieTNZ

    Are Input Photons #2 and #3 Still Entangled After Going Through a Beam Splitter?

    In regards to the attached image; If the input photons were, for input b = photon #2, and for input c = photon #3, where: photon #1 and #2, and #3 and #4 are entangled as |H>|V> + |V>|H>, for the outputs:|H>(b’)|H>(b’) - |V>(b’)|V>(b’) + |H>(c’)|H>(c’) - |V>(c’)|V>(c’) + H(b’)|V>(c’) -...
  20. H

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  21. W

    Deflection of L Shaped Cantilever Beam

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  22. H

    Polarization of Reflected Beam

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  23. A

    Loaded beam in compression? (buckles?)

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  24. S

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  25. M

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  26. B

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  27. S

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  28. S

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  29. G

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  30. J

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  31. S

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  32. H

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  33. P

    Optics: Determining focal length for collimated beam

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  34. K

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  35. M

    Please i with Beam Deflection problem

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  36. N

    Refraction of a beam of parallel light in a thick-walled wine goblet

    Homework Statement A thick-walled wine goblet sitting on a table can be considered to be a hollow glass sphere with an outer radius of 4.00 cm and an inner radius of 3.40 cm. The index of refraction of the goblet glass is 1.50. A) A beam of parallel light rays enters the side of the empty...
  37. StevieTNZ

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  38. D

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  39. K

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  40. S

    How do I calculate the bending moment in a beam for my ramp design?

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  41. E

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  42. S

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    Homework Statement Find the Fay this is static equilibrium so ƩF=0 and ƩM=0 Homework Equations ƩMa=0 = 2x5 + (-4x25) + (2Fby) Fby= 45 Newtons Using ƩFy we get Fay= impossible! Now if take the moment about point B i get ƩMb=0 = (4x5)+(-2x25)+2Fay Fay = 15kN Using ƩFy we get...
  43. D

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  44. N

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  45. J

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  46. O

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  47. C

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  48. R

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  49. photonkid

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  50. T

    LED Light - Beam Charactoristic?

    For some of the high powered LED lights, the beam seems to have bright and dimmer sections along its length when projected through air. They seem to be regularly spaced rather than random. Some people have described it as looking as though the beam would get thinner and wider along its...
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