Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

Register Log in
  • 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 pyseng

  1. pyseng

    Wind loads on buildings with non-orthogonal walls

    I am struggling to decide on the most appropriate way to apply wind loads to a structure that has a significant skewed portion and am curious as to how others might approach it. I have attached a prototype of a floor layout to demonstrate my situation. The structure isn't large enough to require...
  2. pyseng

    Problem with LRFD Combination 3 (ASCE 7-10)

    I definitely agree that there will always be edge cases, but I disagree that the benefit of the 3D model is to catch those cases, that is the responsibility of the designer in my opinion. One interesting note there is that RAM Structural doesn't even let you consider Roof Live Load and Snow, you...
  3. pyseng

    Problem with LRFD Combination 3 (ASCE 7-10)

    I was grouping the load combinations together based on their primary load effect, mainly for convenience to (hopefully) better articulate my point. The primary load effect in LRFD Load Combination #2 is snow. Because it is a primary load case, snow drift is required to be considered. By...
  4. pyseng

    Problem with LRFD Combination 3 (ASCE 7-10)

    I am not trying to start another LRFD vs ASD discussion here. But I was just wondering if anyone can either validate my problem or offer any insight that might help me make better sense of this issue. I have reached out to the ASCE committee on this issue but they didn't seem to quite understand...
  5. pyseng

    Practical Maximum Spread Footing Size

    KootK, thank you. As you seem to note, Points 1, 2 and 3 require either A) an architect with above average understanding of structural engineering or B) a very productive pre-design meeting. Both of which are unicorns in my limited experience. As for Point 4, that's basically the direction I'm...
  6. pyseng

    Practical Maximum Spread Footing Size

    Thank you for the responses, looking back at my initial post, I definitely made a lot of assumptions regarding the particular situation I'm in. That's my bad.
  7. pyseng

    Practical Maximum Spread Footing Size

    We typically do relatively low-rise steel buildings. The AISC System Design Example (v15) is actually very nearly what we typically do. In fact, I'm planning on using that example as a demo for a future discussion. In terms of context, I would say that I've gotten funny looks from both my...
  8. pyseng

    Practical Maximum Spread Footing Size

    I'm sorry, was this an unreasonable question? The reason I ask is that I often find I am asked to design an isolated spread footing for something like a braced frame foundation. My designs always come out rather large because I need a lot of dead load for the overturning load case. As such, my...
  9. pyseng

    Practical Maximum Spread Footing Size

    As the title suggests, I am curious to know what others use as a "rule of thumb" for the maximum size (square side length and/or thickness) of an individual spread footing before they move on to a different foundation system. Thanks!
  10. pyseng

    Optimum Design of RC Shells and Slab Question

    I have recently been interested in using FEA to model and design complex concrete shapes. Through my research, I've found that the Sandwich model, used by SAP2000 and ?Eurocode?, is very logically consistent to me and I would be comfortable using it under the so-called "engineering...
  11. pyseng

    Demand forces from FE plate results - Concrete design

    Thank you, HTURKAK. I will certainly take a look at some of those resources. I have an irregular mesh because the tank is actually a 6-sided diamond shape, with an irregular pile layout, so it just lends itself nicely to parametric mesh generation (which, I have to give credit where credit is...
  12. pyseng

    Demand forces from FE plate results - Concrete design

    Definitely agree on your first point, steveh49. My issue isn't that my reinforcement changes orientation, the issue is that, due to geometric constraints, the local axes of my FE plates are not all aligned with my reinforcement orientation. And, my software does not allow one to reorient plate...
  13. pyseng

    Demand forces from FE plate results - Concrete design

    Very much appreciate the replies. A lot to unpack here but it seems the fundamental issue here is the facilities of STAAD. If I may go on a bit of a rant about STAAD and Bentley, I would like to preface this by saying that I am in no way affiliated with any FE software company The first thing...
  14. pyseng

    Demand forces from FE plate results - Concrete design

    Thank you for the reply. I certainly agree that pictures help, but man, plate element diagrams and force transformations get messy really quickly. Just to address a couple of your points: 1) Ideally, I would like to be able to set the local axis of my plate elements to be in the direction of my...
  15. pyseng

    Demand forces from FE plate results - Concrete design

    I'm working through a design for a partially underground concrete tank. The structure is modelled using plate elements in STAAD. I am having difficulty rationalizing the proper way to transform the plate element forces (Sx, Sy, Sxy, Mx, My, Mxy, SQx, SQy) into proper design forces. My problem is...
See more

Part and Inventory Search

Back
Top