Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations cowski on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Recent content by hernma

  1. hernma

    Allowable stress and deflection on multiple-span supports

    Acob: For any beam with moments Ml and Mr, use the following expressions: E*I*Dx = ( p*L^3/24 + L/3 ( Ml + Mr/2 )) X – mx Where: Dx = Deflection at a distance X from the left support p = T/m (force/length) mx = X^3/6 ( Rl –p*X/4 ) + Ml*X^2/2 Rl = p*L/2 – (Ml-Mr)/L Ml ( Mr ) =...
  2. hernma

    centre of rigidity of a building

    cyak: The expressions presented by you to find the centre of rigidity are correct. I think it is better to consider the frames as a whole. When you apply a horizontal force at the centre of rigidity of a floor building, you get only horizontal displacement in the direction of the applied...
  3. hernma

    Moment Distribution in Continuous Concrete Members

    rowe: Since the characteristic of a plastic hinge – that is not supposed to reach at- is maintain the full capacity of resistant moment, please can you develop your idea that it is "in between a trully "continuous" beam and a "simply supported" beam"?
  4. hernma

    centre of rigidity of a building

    Sorry… I misspelt, it is “talking about” instead of “taking about”…
  5. hernma

    centre of rigidity of a building

    Please note, when I mention "displacement", I am taking about relative displacement between the top and the bottom of columns at each level. Regards.
  6. hernma

    centre of rigidity of a building

    An approximate method consists in applying the total of the static seismic force at each of the planar frames. Since the forces are the same, the lateral floor rigidities at each level can be found dividing the (same) accumulated force (from top to level) by the displacement. Alternatively...
  7. hernma

    fee for structural design

    Just to give an idea, we charge from 1 to 1.5% of the net value of the construction, or the 4% of the value of the structure, whichever is higher. Of course, due consideration is given to different factors, such as those very well expressed by Lutfi. I agree completely, that quality in the job...
  8. hernma

    Slab pour sequence

    aun: If I understand correctly, you have your beams ready and what is missing is the pouring of the slab. Two points: the main reinforcement of the slab is radial (or perpendicular to traffic), and in the two central supports, fixed or not to the columns, there must be some negative...
  9. hernma

    Really good information for Structural Engineers available at the foll

    amirjehazi try this one: http://www.wsdot.wa.gov/fasc/EngineeringPublications/library.htm
  10. hernma

    The metric system of units is best !!!

    I was in Canada once , but as a tourist, so I didn’t have the opportunity of buying anything by weight, and I would be aware of the exception , definition or synonymous given in “SI unit rules and style conventions”: “# 19: WEIGHT vs. MASS When the word “weight” is used, the intended...
  11. hernma

    The metric system of units is best !!!

    We have to differentiate the SI system from the metric or thecnical system. I agree complete in using the metric system, it is simple and easy to use, as many of you have pointed out. The SI system is not so simple and is not popular in Latin America, even this countries have adopted it...
  12. hernma

    Shear in flat slabs

    As a second point, I mention the modelling followed by ACI when the shear is checked as a beam in one direction, assuming the critical section extends across the entire width. According to 11.12, the flat slab works in exactly the same form as does a footing, taking the full width as...
  13. hernma

    Tension flange restraint

    Lutfi: Please, can you give me more information about the book by McGuire (editorial, year...). Thank you.
  14. hernma

    Shear in flat slabs

    ARH and benishak, thank you for your comments. ARH: when you mention that the concrete crushes, I agree with you, because it means that you have a flexure mechanism of failure due to the extension of the upper steel, and this is what I have observed. I think it is also due to the torsion of...
  15. hernma

    KIPS

    Ingenuity is correct: 1 Kip = 4.45 kN. Here, some additional information: 1 pound (lb) = 453.59 grs, or 1 Kg = 2.205 lb Kg = 9.80665 N = 2.205 lb, from where: 1 lb = 4.448 N 1000 lb = Kip = 4.448 N x 1000 = 4.448 kN Kg/ cm2 = 14.223 psi psi = 0.0703 Kg/ cm2 (this value is more exact) N/m2=...

Part and Inventory Search