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  1. Lomarandil

    Suspension Bridge Design Examples

    Note that (last time I read it, which I think was the 5th edition), the B2P manual linked by Little Inch covered suspended bridges, not true suspension bridges. Still lots of good material there, but wouldn't want the difference to trip you up.
  2. Lomarandil

    Remote SE Work

    For experienced and mature engineers -- absolutely. For young engineers it can be a real handicap.
  3. Lomarandil

    Wind loading during deck pour/curing

    I agree that 20mph (3s gust, service) concurrent with wet concrete is appropriate for that very reason -- the evaporation limit. About half the time I'll use that, sometimes I'll stick with the 0-6wk wind for my own convenience (e.g. the bridge isn't sensitive to the difference) or to build in a...
  4. Lomarandil

    Equate CBR value to kN/m2

    Sure thing -- it's an exercise in managing risk. Some sites have naturally lower risk (the "can I drive my truck over it?" test). Some plants are small enough to naturally work out. My niche means I tend to be evaluating 300t+ cranes swinging (and sometimes walking with) 75t picks. In those...
  5. Lomarandil

    Equate CBR value to kN/m2

    Exactly, and once you're specifying crane pads of any decent size under the outrigger, CJL's concern about depth of influence is valid. Some additional evaluation should be performed to ensure the near-surface capacity is similar to or less than the capacity deeper below grade. CIRIA and TWf...
  6. Lomarandil

    Lifting a Precast beam 12 m length

    To calculate those tension stresses during transport and lifting, refer to the excellent articles by Mast (which are now incorporated into some PCI materials, but I find Mast's original articles do a better job explaining the reasoning). There are more potential causes of tensile stresses than...
  7. Lomarandil

    Understanding ACI Design Example

    Responding to your #2 -- some soil conditions have different (vertical) bearing capacities depending on the duration of loading (depending on water table, settlement effects, etc). This is specific to a site and accounting for this variability is falling out of common practice (at least from...
  8. Lomarandil

    Lateral Loading for Fall Arrest Gantry Beams

    Deflections under fall arrest loading aren't given a hard limit by any code I've seen. As you note, a few conditions that may limit what you want: P-d effects on your structure Excessive vertical deflection could reduce the clear fall distance before a worker falls into a hazard below...
  9. Lomarandil

    How will you assess a bridge for oversized load transportation?

    My experience is similar to BridgeSmith (assuming a relatively simple girder bridge). You'll often need to check multiple elements of the bridge structure using separate assumptions (e.g. wheel loads can be shared across the deck using an AASHTO equivalent deck strip, but are usually applied...
  10. Lomarandil

    Load bearing capacity of a 40' seacan

    https://www.eng-tips.com/threads/shipping-containers.442738/
  11. Lomarandil

    Concrete cover pile cap

    Cover is counted from the outermost bar, which is usually a tie bar when present
  12. Lomarandil

    Foundation design for a challenging site: old foundation wall, potential differential settlement, and unknown foundation depth

    Oof, you're not kidding. We can think about some rational, conservative assumptions to make, but I'd be pressing hard for more investigation if that's at all possible. You'll end up saving the client money in the long run.
  13. Lomarandil

    SAP2000 Truss Bridge Bracing

    Lateral x-bracing in many truss bridges is detailed and intended to act as tension bracing. While the other half of the X may i initially attract some compression, it quickly elastically buckles and becomes ineffective (until the lateral load is removed). I haven't used SAP for a long time --...
  14. Lomarandil

    Propped Cantilever Beam LTB AISC

    AISC is less thorough considering LTB in cantilever beams than BS or Eurocode provisions. To meet the minimum requirements of the code, you simply use Cb=1 and Lb = L. AISC assumes full torsional restraint at the support and full depth stiffeners at the ends of cantilevers (unless some other...
  15. Lomarandil

    Stitch Weld - Length Calculation

    I'm another in the camp of "it comes out in the wash". Obviously keep stitch lengths reasonable (I tend to use 6x or 8x leg size rather than the 4x minimum), but I don't otherwise add any extra length beyond what I need to get the utilization into my target range.
  16. Lomarandil

    Retrofit of stub abutment

    You could connect with epoxied dowels, or PT rods passing through the existing abutment and clamping your new cap to the abutment. You could install low-headroom piles through holes cored in the existing abutment, then grout them in place. If your girders can handle a relocated support, I like...
  17. Lomarandil

    Is there such a requirement as minimum length for groove welds?

    I'm similarly not aware of a specific requirement that would apply to flare bevel welds, but I would consider it similar enough to a fillet weld that I'd stick to J2.2b(c) as 271828 mentioned
  18. Lomarandil

    PEMB continuous footing to resist sliding

    I'll also vote for using it, but being sure to consider lateral spread/deflections under service as bones mentioned and considering what types of joints may be present between the footings. In some cases those end up being isolated to manage relative vertical deflections, which can limit how...
  19. Lomarandil

    Strong River bridge collapse in Mississippi

    3DDave -- that's usually the easiest approach, but construction sequences and methods rarely survive 50 years of county records offices.

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