I've been to a few indoor ranges that only allowed soft-point bullets. Presumably because the steel jackets will penetrate much farther / higher chance of ricochet. Probably worth clarifying with the client whether that'll be the case for their range. Though you may want to design for the "load...
The added bonus of using F1487 is that you can then call your bed "Playground Equipment for Public Use".
Instinctively I'd probably add one or two more 2x4s and reduce your spacing by that much, just to be sure. Maybe not if you have a good box spring above those 2x4. If you're just putting a...
How far out is your cantilever? You'll want to think of the whole bed flipping over when two people are sitting one one side. A 40psf UDL won't really capture that. I'd personally look at a 400-500 lb load applied right at the end of your cantilevered "joists". Maybe more if you're expecting a...
I think you're looking for the Constant Amplitude Fatigue Limit (CAFL). Look at EN1993-1-9. You'll match your specific details to the ones shown in Table 8.1, and find the associated design curve (Figure 7.1). You'll see it goes flat at some point - the stress range associated with that is your...
Yochael,
I agree. these generic equations should definitely be taken with a grain of salt. As I mentioned with a smaller truck they give you wheel widths that are better suited for a bike...
Would highly recommend going through Chapter 3 of the LRFD spec, you'll see the load factor varies...
In AASHTO LRFD Code 9th edition (2020):
These get a bit funky when you have smaller trucks - eg the H5 truck used in pedestrian bridges would theoretically have a 1.25" wide front wheel...
It really depends on your specific equipment - if you contact the manufacturer they should be able to give you info on natural frequency restrictions. If there's no heavy moving parts it may not be an issue.
If it's a matter of measurement sensitivity, it may also be in terms of allowable...
I don't think a non-conductive washer will do much with self-drilling screws - the threads will still be in contact. You'd use those more typically in bolted connections between dissimilar metals. Often you might even put in a sleeve to make sure there's zero contact.
If you're going with...
Self-drilling screws are just regular screws that drill their own pilot hole. I think you should be fine using the regular screw formulas, with your hole size taken as the drill point diameter (should be on the data sheet for the screws).
Also if this is for cladding, be 100% sure you're dealing with 6061-T6. Ask to see the MTRs. If you have the chance to visit the site, bring a piece of known 6061-T6 and see if you can scratch/gouge the metal. 6063-T5 is very common in the enclosure world and it's much, much weaker (Fy 110, Fu...
If you're in Canada, CSA S157 does have a relatively easy formula to calculate screw pullout strength in aluminum. Depending on your thickness the strength is controlled by yield or ultimate strength. In the US you'd be looking at the Aluminum Design Manual (uses the same formula as S157) and in...
Thought you guys might like an update on this - we wanted to have further certainty so we decided to do a few quick tests to validate our assumptions. Perks of having a press at the office :-) We were also able to modify the bracket to have the moment applied closer to center.
Our "pry" test...
What kind of loads will this be exposed to? Anything that'll cycle through that torsion more than once or twice a month and I'd be expecting it to fatigue out very quickly. The crack is essentially already initiated at the root and you'll never know how fast it's growing until it just snaps one...
Any chance you can place them side by side and have cover plates on both side to join them? You can adjust the cover plate thickness as required to get enough stiffness / capacity. You also won't need to worry about LTB in that case. This'd let you save a good chunk on welding / prep /...
I think most building codes will specifically say that you need to consider the case with full live load on both sides (max axial load), and the case with live load on only one side (less axial, higher moment). Snow & wind will have similar provisions as well, though you might have a 25% on the...
Thanks, jjl! You're right, I will contact the designer and see what they typically do. And for letting me know about the AAMA slip criteria - I wasn't aware of it. Will go through that check. This is great!
Thank you all for your replies! Much appreciated!
First of all I apologize as I made some mistakes in my original drawing - there is a lesson learned there on my side about making drawings too quickly in Paint... The vertical load is actually only 200 lb and the screw spacing is 2", not 1.5"...
I have been tasked with designing sunshades for an aluminum curtain wall. While everything seemed fine at first, some last minute changes now have me questioning my judgement and I'd like to ask your opinion on this.
The sunshades are connected to an aluminum bracket that screws into the...
My understanding is that the buckling formulas incorporate an additional factor of safety to account for imperfections / accidental eccentricities. That'd be why you're not getting your full 50 ksi with the formulas. Imperfections wouldn't have much of an effect at short lengths. Eccentricities...
KootK - good point about the slip in connection. Agreed on still checking for fasteners though!
With 11-7/8 joists and a W10 you should have enough space to fit at least a 1" thick flat bar over your top plate to spread the load - should be plenty to make sure your top plates don't crush.
