Nice discussion. Just want to discuss the units being used in the equation VQ/I. V is shear in pounds, Q is the first moment about the neutral axis in inches^3, and I is the moment of inertia in inches^4. It looks like there is an extra inch in the denominator - unless V is actually the vertical...
I have real heart burn considering an 8" CMU wall as cladding. If you went to 12" CMU in a bearing wall condition it wouldn't be cladding and the wind sure wouldn't know the difference. Call the building department and get their thoughts on this. Lots of engineer don't like the current wind...
You mentioned the sounds occur when you walk on the plywood ADJACENT to the beam. Is the depth of the hanger such that the top of the hanger is flush, or lower than the top of joist. If it's higher than the top of the joist the plywood will need to rise up to pass over the hanger top flange. Any...
KootenanyKid - The assumption is the other side of the FBD is at least as good as the side the side you are working on. If it's better, then the weakest side is what you should be calculating. Suppose you had a concrete beam cantilevered off the flange of a really heavy steel column. Would you...
BA - I think you're right, what with the deflection of the angle getting smaller as the thickness increases. You'd need to check the slope of the deflected angle leg against the slope of the compressed concrete to find out where the center of contact occurs. In the case of a really long angle...
0.85 - - sounds like the "j" part of jd when designing in WSD concrete. For balanced steel ratios "j" is 0.85. I think it's as simple as that. Of course if you recalculated using the actual bolt tension you would get a "j" value much closer to 1.00. But it is a plan checker, give him what he...
Don't know who came up with this but it's nice to have it around when I'm feeling smug.
"Structural engineering is the art of molding materials we do not fully understand into shapes we cannot precisely analyze so as to withstand forces we cannot realistically assess in such a way that the...
K-kid, You mentioned a base plate. Is this a column on a footing. If so they will probably double nut it for erection and mess up your assumptions. Maybe limit the base plate grout to the area between bolts, or just under the column. this could become a strange looking detail.
Old CA SE
In the States (Peoples Republic of CA) the Hilti and Simpson engineers have both produced worked out examples. Check with your local rep's.
Question: why would you choose to put a bolt in a crack? Why not make a large bracket and put the bolt in an uncracked area?
Old CA SE
Mike, If you're worried take Ron's advice. We had a drunk climb over a 14'-0" high chain link fence at a high school we did years ago, then jumped off the diving board into the empty pool. Darwin Award for sure. The judge threw the law suit out of court, thank God.
Did another project where we...
Why not check it both ways and see how much difference there is. There might not be enough to be worrying about. You'll sleep better if your design goes to the column web and the cost difference will most likely be lost during bidding.
Old CA SE
We used to design pools before our E&O carrier made us quit. Seems there were problems with contractors agreeing to build pools on hillsides, kind of like this one. In California, fully grouted masonry walls go for fourteen dollars per square foot - Union, before the economy collapsed. Non union...
First rule of house framing - Design the way the framers will try to build it, if they don't look at the details.
Yeah, I know you're the engineer and they SHOULD build it like your details, BUT you'll just wind up having to justify what got built instead of insisting it be torn out and done...
Old, old (1960's) bond value for plain rebar (not deformed) was 60 psi (80 psi for deformed bars). This of course assumed clean steel surface (no oil or paint) and only a very little evidence of surface rust. If it was good enough for large projects (Hoover Dam, etc) it must have been close to...
Ok - I can hear the laughing now but, I still use Lotus 123 with imported stardard sketches (usually *.PIC or *.CGM files, *.BMP files work but inflate the file size too much). I've been doing this for 20 years now and the best kind of "one use sketch" I've found is a small yellow post-it note...
Robertson UKX 12-12 cellular steel deck, 1.5" deep sec 21 deck with a bottom plate welded on, 12ga corrugations with 12ga bottom plate. Does that sound like what you have? I=1.373, s=1.353, allowable end reaction = 8600#. Should be able to get this data from Robertson's site, if they are still...
Joe, your colored stress diagram doesn't indicate the same member that the picture shows as failed. The failed member in the picture is the green vertical to the left of the one your note points to. The failed vertical in the picture has a pair of knots in it, small to be sure, but close...
