Recent content by Maturin

I am looking for the manufacturer of the following concrete coil inserts: PAI-15 and FCL-5. They were specified for concrete covers, which were constructed back in the mid to late 1970's. I have contacted various manufacturers but have had no luck. Does anybody recognize these inserts? Thanks.

Thanks JStephen. The beam with a standard ladder is a good idea that I hadn't considered.

Thanks for the responses. The ladder (not handrail) is a permanent installation and is replacing an existing ladder. The ladder sway that workers are currently experiencing is in the plane of the ladder (i.e. parallel to the rungs). Out-of-plane direction is not a problem. The current side...

I am designing a 30' ladder (approx) that will not have any intermediate supports along its height. Is there a rule of thumb regarding the required stiffness of the ladder side rails to satisfy serviceability requirements (i.e. ladder does not shake or sway excessively to cause discomfort to the...

I did some approximate preliminary calculations and the weld is overstressed under the worst loading condition. It's not really that difficult to calculate as I assume that there is a fixed connection at the web and at the weld line and a point of inflection in between (similar to bolt prying...

Thanks for the comments. There appears to be strong agreement that this connection detail should never be used. I retract the second comment in my original post as I don't think there is any configuration where the weld would not be overstressed.

This is an existing detail that I'm evaluating. If I was desiging it from scratch then bolting the flanges would be my preference.

Attached is a sketch that shows a small W-section connected to a larger W-section by fillet welds at the flange tips. The smaller beam is relatively short and transfers a tension load to the larger beam. The welds are the only connections between the beams (i.e. no bolts, end plates, etc.). The...

Thanks for all the responses. Fegenbush, the link you provided to AISC recommended field fixes is very useful and it does suggest analysing the nut engagement as an option to dealing with short anchors. Thanks.

Can anyone see any issues with calculating the thread capacity of a anchor bolt nut that is not fully engaged and comparing it to the applied load to determine if it is acceptable? The anchors are 1" diameter Red Head anchors and are oversized for the loads they will see (approximately a 3:1...

Thanks RB1957. When I mentioned circumferential bending I was referring to the transverse direction (i.e. bending around the duct circumference). I'm not really concerned about longitudinal bending.

Thanks for your response jdgengineer.My question is more about the localized load effects at the support. If it is determined that the load at the support is 1500# then how is that load transferred to the support. Is there a uniform radial compression load between the strap and duct over the...

I'm analyzing some trapeze hanger supports for a 72" diameter duct and I'm not sure about the load distribution from the ducting to the hangers. The hangers are semi-circular straps, unreinforced, attached to 3/8" hanger rods while the ducting is 12 ga. thick. Would the duct self-weight be...

Is there any reason why ASTM A193 heavy hex bolts can not be used in long slotted connections?

Is a parapet applicable given that the staging does not extend above the roof line and the wall is 16' deep? My reference is the NBCC (National Buiding Code of Canada) and it doesn't discuss parapets directly. What pressure coefficients (+) and (-) typically act on a parapet?