Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

Search results for query: *

  • Users: meca
  • Order by date
  1. meca

    ASCE 7-10/16 Flexible Gust Factor

    Reference Thread: thread176-453592 I ran across this thread referenced above which has been closed; however, it was a good question and it didn't appear that anyone had answered the original post. I had the same question/concern as the original poster, and so I researched this topic. I...
  2. meca

    Bending moment in a Pendulum with Spring

    Thanks to all. Even though it looks like homework, it's not. It's a type of damping device, and I'm trying to determine how to properly size the beam. I've created a finite element model that gives some stresses, but the hand calculations results are an order of magnitude higher. I'm trying...
  3. meca

    Bending moment in a Pendulum with Spring

    I know this isn't the conventional structural question, but I haven't had any response in the vibration forum. The question is a mix of vibration and stress. I have a pendulum with a spring attached. I can determine a relationship to predict the natural frequency of the system. Where I'm...
  4. meca

    Bending Moment in Pendulum with Spring

    I'm not sure of the best forum to post this question, so I thought I would try here. I have a pendulum with a spring attached. I can determine a relationship to predict the natural frequency of the system. Where I'm having trouble is finding a relationship to predict the maximum bending...
  5. meca

    ASCE 7 - Natural Frequency in Each Direction

    If a structure is flexible (NF < 1 Hz), then we must calculate the flexible gust factor. If the structure has a stiffness which is significantly different in each direction, do we still base the gust factor on the lowest natural frequency for the entire structure? Or is the intent to...
  6. meca

    A-212-A?

    Thank you, this is very helpful information.
  7. meca

    A-212-A?

    I am working on Gasoline Storage Sphere built sometime in the 60's and they have indicated the material is A-212-A. I have found lots of information on A-212-B, but I can't find any properties for A-212-A. Can anyone tell me the difference between Grade A and B? Are spheres usually designed...
  8. meca

    Use API-510 to Stamp non-ASME Code vessel

    I have a pressure vessel that was not originally designed or constructed to ASME Sec. VIII, Div. 1. It wasn't designed or constructed to any code that I can determine. In API-510 Para 7.7 there is a section for "Evaluation of Existing Equipment with Minimal Documentation". I've followed this...
  9. meca

    Brick Arch

    Here is a link to some pictures to show the construction at various stages, which I think might be more illustrative than my 2D sketch. http://www.mecaenterprises.com/downloads/ArchPics.pdf
  10. meca

    Brick Arch

    I realized I made a mistake in my reactions. The vertical load is only 3,500 lbs, but the thrust is 1,300 lbs. http://www.mecaenterprises.com/downloads/ArchModel2.pdf If I model as an arched beam with total of 7,000 lbs uniformly distributed, then I get a thrust of aobut 8,000 lbs. I'm...
  11. meca

    Brick Arch

    Thank you to everyone for all of the helpful comments and suggestions. No design was done on this arch, it was just built by the masonry guys, and they believe it is fine (shocking). There is no wood beam, truss, structural steel, or any reinforcement inside of the arch and columns. I've...
  12. meca

    Brick Arch

    My main concern is structural integrity, I can live with the appearance. I have no experience with brick work, can anyone comment on whether the arch "Looks" like it is adequate? I'm just asking for a gut feel based upon your experience, on whether the arch looks like it is adequate to...
  13. meca

    Brick Arch

    I design steel frequently, but I'm not sure how to analyze this situation. I can model an Arch in StaadPro, but I'm not sure what material and section properties to use to simulate the arch? Once I determine the thrust load, I'm not sure how to determine if that is acceptable. Hokie66, what...
  14. meca

    damping ratio (beta) for use in calculating gust effect factor (G)

    mpdst11, What type of structure are you analyzing? Are you sure it classifies as a flexible structure (NF < 1 Hz)?
  15. meca

    Brick Arch

    I am building a home, and have a brick arch over an entry way. Due to a mistake, the arch is wider and flatter than originally intended. I don't have any experience with masonry, and was looking for some guidance on how to confirm that this arch is adequate to support the weight of the brick...
  16. meca

    Include Liquid in Overturning?

    I saw that, but I have an anchored tank. Is there any direciton in the code for an anchored tank?
  17. meca

    Include Liquid in Overturning?

    IFRs, I'm looking at API-650 (11th Edition - June 2007) Para 5.11, and I don't see anything about how much liquid to assume for an anchored tank?
  18. meca

    Include Liquid in Overturning?

    I have a question regarding tank design per API-650. I have a small (30 ft OAH x 12.5 ft OD) tank that is shop fabricated. The tank is in a very high wind zone, and I am verifying that the tank is adequate for overturning. My question is whether you must consider the tank to be empty (no...
  19. meca

    ERECTION PROCEDURE FOR BOILER STACK

    My company specializes in stack design, and the earlier posts are correct. You need to know how the stack was designed to be lifted, before a procedure can be written. The lift procedure is usually prepared by the company performing the lift, but they take into consideration the way in which...
  20. meca

    Pipe Temp - Wind Outside &amp; Hot Gas Inside

    I have a pipe that has a hot gas (air at low velocity) on the inside (800 Deg. F). On the outside of the pipe I have a 90 mph wind blowing across the pipe (70 Deg. F). I’m trying to determine the average steel temperature on the pipe itself. The pipe itself is Carbon Steel 70" OD and 0.3125"...
Back
Top