Yes - having read what Blodgett has to say on it, i think i will be asking them to weld up a diagonal stiffener across the eaves mitre line and a vertical one at the apex. After all they'll be grinding off the existing cleats for the rails to weld new ones on so it shouldnt be a big deal.
Apologies for going missing on my own thread, got dragged into fighting a different fire as you do. Can't believe I didnt think to check Blodgett, i even used it for something else this week. I'll start there - amazingly a second instance of this has come up this week, what are the chances..
Hi all,
Hopefully someone can help me (or confirm what I already think i know). I am running an assessment on an existing steel portal which has been taken down and is being erected in a new location. The apex and the eaves, rather than being bolted, are welded like the image below - there is a...
I'm hoping someone can help me with this, I am stumped.
I have some calcs to check, relating to a falling body onto a wire suspended platform. The aim is to check the equivalent impact force (P) in the wire. The calcs go as follows, and I can't figure out how the formula has been re-arranged...
Some great advice here guys, it is all appreciated. To just comment on a few points:
P delta checks - agreed. When I take it 'to the computer' I will make sure the analysis is second order. At this stage I am trying to lay it out by hand so that I know that the answers that come out of the pc...
Hi all. I have a problem I need some advice on.
I am designing a thing for a client where they are installing a truck on top of a totem pole outside their truck factory, as a feature at the entrance. So this thing will be a 6000Kg truck tilted at 30 degrees (as if driving down a hill) on top of...
Doug,
I have only just noticed your reply and thought I would acknowledge your effort in writing the spreadsheet to check it out for me - really appreciated, thanks. I've downloaded it and will be giving it a once over, I've wanted to pick up a few tips on programming the stiffness method so it...
Self weight is off! I'm glad that at least I have the analysis principle right now. Being out by a kN is not a big deal but i'd be worried if I was dealing with forces an order of magnitude greater.
And the appreciation for not believing the computer is appreciated!
OK, so I thought I had cracked it. Attached is my work through of the example posted previous - the results come out pretty close. To be extra sure I ran a second check and I got different answers to 'the machine'! I will put the screen grab from Robot in the next post as I can only add one file...
True, perhaps I am a bit hasty in calling it wrong. It is after all 99% of the software analysis which is more than close enough! Also when I work out F2 using 16.4 x cos 47.54 i get 11.08kN which again is 99%.
My 'problem' with it is that I think the vertical component of reaction at 4 is...
Ok, I am not to proud to admit I am being an idiot. I have attached how I would go about this and perhaps someone can point out the obvious!
I have drawn out the geometry in the top half. At the bottom, I have started with N4 and immediately get it wrong - I know it wrong because I have a...
1 and 2 are two different members. They will be connected at Node 3.
In my time zone its late so I will go through the responses you all have very kindly given me in the morning and respond.
I was thinking that too, but you can change the pin at 1 for an X-axis only restraint without changing the results of the computer analysis, leaving three unknowns - Hz at 1 and Vt at 3 and 4? (Have only just done this since the OP by the way!)
I am tying myself up in knots with this one. I have a system like the picture to assess. There are a variety of geometric configurations so i was planning to plug it all into a spreadsheet, but I am not happy that I am programming it right. So, I modelled one scenario and I cannot mirror the...
Thanks guys - the work is a generic check of a specific component to be used within a scaffold system, thus is independent of location. I will need to review the relevant scaffold codes of course, but it sounds like from what was said above the AISC spec for structural steel buildings is a good...