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  1. JMorrison

    % of reinforcement in column

    If the concern is that you're actually under 0.5%, check your design (neglecting the steel) against the ACI provisions for structural plain concrete (318-05 chp 22). If it works as SPC, the fact that you actually have some reinforcement there is immaterial. If the question is whether 0.5% is...
  2. JMorrison

    Severe exposure to unknown substances

    The epoxy coated bar would probably help out a bit, and I'll look into the local availability of silica fume. Membranes and other exterior-based protection - we may be able to use 'em for the above-water portions to protect against splash / tides - and that may be a good solution for protecting...
  3. JMorrison

    RAM Steel Analysis

    You've probably already discovered this answer on your own, but in the interest of completion for others with similar questions - from Manager, check out the 'criteria' menu on the left. In current versions, you have the ability to specify exactly what self-weights the program calculates. Use...
  4. JMorrison

    Severe exposure to unknown substances

    Got a bit of a fun one here - it's a single-story concrete moment frame, supported on caissons, with about half of the building extending out over the Anacostia river here in DC - so half of the building columns are going to be exposed to running water from one of the most polluted waterways in...
  5. JMorrison

    RAM Steel "Fatal Error: No Beam Loop Intersection Found"

    I know I've seen that one, trying to bring the ol' memory online here... Does the error occur on the same member number every time? If so, do a quick 'renumber members' and see if the error occurs on the same member (with the new number). Once you find the member that's a problem, take a...
  6. JMorrison

    deep grout beds under steel columns

    The anchor rods were spec'd with 18" embedment plus 2" grout, and for the loads we're seeing here we can easily live with only 13"... and the bearing surface isn't cast yet so we can just set them high. Adding additional thickness of plate should work, and the fabrication should be pretty quick...
  7. JMorrison

    deep grout beds under steel columns

    I've got a couple columns located within a slab depression, and the revised base plate elevation didn't get picked up on shops... which leaves about 7" between bottom of base plate and top of bearing surface. Column loads are on the order of 400-450k, shear/moment are not concerns at this...
  8. JMorrison

    Steel Floor Plate

    Check McNichols - they're one of the better known producers of gratings / checkered plates - if it's out there they'll likely have it. http://www.mcnichols.com
  9. JMorrison

    Online Timber & Masonry Design Course (or books)

    "Reinforced Masonry Design" by Schneider & Dickey is another great reference - it's out of print and based on older codes (last revision was '93) - but it's well written with concise examples and should give you a good grasp of fundamentals. Amazon is selling a paperback reprint, in case you...
  10. JMorrison

    Need Plotter/printer advice

    Need to know a bit more about your requirements and budget before making a tailored recommendation... We're using an HP Designjet 1050c - it runs about 15-20 30x42 sheets an hour, fully networked, handles up to 36" rolls, with decent print quality. We're printing an average of 50-75 pages/day...
  11. JMorrison

    cannot delete layers

    Assuming that you're trying to delete a layer that you've created (either directly or as a part of your office standards) and not one of the cases directly mentioned (layer 0, defpoints, current, xref, etc)... Odds are that you've got a block defined somewhere in the drawing that contains an...
  12. JMorrison

    Designating Cross Bracing on a Space Frame

    Yes, if you run Staad without the MEMBER TENSION command, you will have forces in both diagonals - this isn't a mistake, and it is a valid design methodology. The decision whether to use C/T bracing or Tension-only bracing is made based on engineering judgement. You can refer to pretty much...
  13. JMorrison

    How to set deflection limit DFF?

    Easiest way I've found to check what's going on if there's excessive deformation at a node, turn on Animate mode if your version of Staad supports it. Once you see a graphic of how the building is actually deflecting, it's usually pretty obvious where the problem is, or where you need to add a...
  14. JMorrison

    Lateral Diaphragm values of 2x decking?

    You'll find a lot of info on this question in the Timber Construction Manual. Typically from what I've seen in decking applications, it isn't so much of a constant diaphragm capacity (like you'd look up for steel deck), but an analysis of weak-axis bending of the decking members as modified by...
  15. JMorrison

    Minimum Reinforcement for Mass Concrete

    If the reinforcing is required to resist design loads, it needs to be located consistantly with your design assumptions. Take a look at ACI 318, chapter 22 (Structural Plain Concrete) - if your stresses are low enough reinforcing might not be required at all, unless you have a waterproofing /...
  16. JMorrison

    Southern Pine (Wet Service Conditions)

    Yep, the only thing that means is that you don't have to apply a Cm adjustment to those species, even if they are used where MC>19%. There is no analagous "increase" for those species available if they're used in dry conditions. This is made a little clearer in the Supplement, look at the...
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