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...
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...
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...
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...
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...
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...
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...
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.
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 --...
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...
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.
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...
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
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...
You're right, it often doesn't get the attention it deserves. And cases like this are tragic.
When done properly, it needn't be risky. Shameless plug here for the best practices guide we published last year https://ascelibrary.org/doi/10.1061/9780784485361
Absolutely. Planning demolition work...
I got into a major disagreement with some French engineers a few years ago about this.
Their position was that because Eurocode prescribes that force needs to be "external", that internal forces like vector component reactions or weight of concrete cannot be used as the "clamping force". It...
