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Recent content by rd78

  1. rd78

    Non Structural Components

    Thanks for that. To clarify, you are saying the exemption may not apply? In this case the issue is non-essential HVAC ductwork already installed followed later by the electrical contractor locating an essential conduit (not sure what, perhaps exit lighting) to cross below the duct. Access may...
  2. rd78

    Non Structural Components

    Hello, I am querying about an interpretation of ASCE 7-2002 as referenced by the NYC code. In 9.6.1 the exceptions indicate components with Ip of 1 are exempt from the provisions of the section for a Category C building. Later it says that one should address these items when failure could...
  3. rd78

    FRP ledge angle

    I can't speak to the thermal break issue, but a comment about the use of FRP here in general ... First of all there are no real "grades" of FRP. As a matter of fact, while processes and profiles may be similar from vendor to vendor they are not automatically interchangeable. It is much like...
  4. rd78

    Pipe Stress Analysis Software - FRP Piping

    I would stick with CII to cut down on the learning curve. The biggest thing is to know what CII is doing with various inputs and what various results mean. Make sure you are very confident of the inputs. In order to join the modern world you have to be prepared to address ISO 14692. Good Luck!
  5. rd78

    BEACH SCOUR CALCULATION DUE TO WAVE ACTION

    Hello, FEMA has a publication (55 I think) that treats scour based on wind/wave. Good Luck.
  6. rd78

    Antenna Deflection Requirement

    Hello- I wonder if some of you RISA Tower users or other experts can help me understand a requirement. The requirement states "maximum sway of 0.4 degrees from the top or 2% of the height, whichever is less". I can certainly calculate the deflection due to wind and compare to 2% of height. I...
  7. rd78

    Breakaway walls

    Try the following- http://www.fema.gov/library/viewRecord.do?id=1722 Design and Construction Guidance for Breakaway Walls Below Elevated Coastal Buildings That provides some prescriptive details you can look at.
  8. rd78

    Fluid Motion in Agitated Tank

    Hello- I don't know if this is the right place to ask, but here goes. I am designing a support system for some equipment suspended within a chemical reaction vessel. I am comfortable with the gravity and buoyancy loads, but am at a loss as to how to determine what lateral loads would apply...
  9. rd78

    Does anyone know any references about design of composite FRP I-beams?

    Regrettably, there is no valid reference. You can look at the old ASCE Plastics Design Manual, the Eurocomp Handbook or even MIL-17. ... But I haven't heard of such a hybrid beam. How would the FRP web be bonded to the aluminum flange? As for local web buckling, you'd have to look at the...
  10. rd78

    asce 7-02

    The R value of 1.25 is probably the strictest reading of the table although a case could be made for 1.5 "Tanks with unanchored and unconstrained flexible base". Intuitively however, fiberglass would seem to be closer to steel in terms of flexibility, ductility, etc. and using the conservative...
  11. rd78

    Seismic assessment - pipework

    Does the piping system has an existing stress analysis for the original design? To what code was it designed? What sizes and operating conditions? You can add seismic accelerations to the operating loads in Caesar II/ Caepipe, etc. You ought to make sure the correct properties for the pipe...
  12. rd78

    Wood Works Design Office 2004

    It's pretty convenient for the simpler repetitive tasks, but not so handy for more custom or complex arrangments. Its mainly due to programming limitations on how it handles complex roofs, walls that don't intersect at 90°, steps in floor elevation, etc. Good luck.
  13. rd78

    Simple Array Addition

    I just tried defining road as a matrix (48x1). Then define subgrade= road+2. It works fine. The result is a matrix with individual values 2 greater than road. You maybe be having a problem using the range variable n.
  14. rd78

    Switching Engineering Fields?, Looking for Advice

    Try looking at firms that design structural items with composite materials. There's a demand for competent composite materials engineers. A couple are: www.FSEInc.com www.ershigs.com
  15. rd78

    ANSYS help - Pacific NW

    Our guy in house is most familiar and comfortable with solid element models. What I need is really some simple shell and beam global models set up in a way that we can modify loads and our in house guy can readily extract info for more detailed models.

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