OVERLAPPING MEMBERS...NEED HELP
OVERLAPPING MEMBERS...NEED HELP
(OP)
Hi guys I've been trying to use a software to model a steel truss where the bottom chord is on top of a concrete beam along its full length. I was able to create the model but the program is issuing a warning message saying that the members are overlapping. Will this affect the analysis and design of the whole structure? Thank you.






RE: OVERLAPPING MEMBERS...NEED HELP
http://www.FerrellEngineering.com
RE: OVERLAPPING MEMBERS...NEED HELP
The actual structure will be like that sir as per plan so I've been trying to model the whole structure according to the plan. Yes the whole bottom chord is on top of the beam and columns at both ends. The bottom chord of the steel truss is only restrained by dowels wrapped & welded to the bottom chord at 1.5m on center. I used to transfer the truss loads to the beams but now I tried modeling the whole structure including the steel trusses and I encountered this error. Any solution in mind sir? thanks for the reply.
RE: OVERLAPPING MEMBERS...NEED HELP
RE: OVERLAPPING MEMBERS...NEED HELP
RE: OVERLAPPING MEMBERS...NEED HELP
RE: OVERLAPPING MEMBERS...NEED HELP
RE: OVERLAPPING MEMBERS...NEED HELP
You might have to look at the problem from this perspective and try to model it as one composite bottom chord of the truss, partial or otherwise...
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: OVERLAPPING MEMBERS...NEED HELP
RE: OVERLAPPING MEMBERS...NEED HELP
Are not the centerline of the concrete beam and the centerline of the truss bottom chord member separated by a definable vertical distance?
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: OVERLAPPING MEMBERS...NEED HELP
RE: OVERLAPPING MEMBERS...NEED HELP
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: OVERLAPPING MEMBERS...NEED HELP
RE: OVERLAPPING MEMBERS...NEED HELP
RE: OVERLAPPING MEMBERS...NEED HELP
RE: OVERLAPPING MEMBERS...NEED HELP
RE: OVERLAPPING MEMBERS...NEED HELP
You could itterate this procedure as many times as you needed to bracket the solution you seek.
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: OVERLAPPING MEMBERS...NEED HELP
Sorry If I didn't get your point with your last comment. If I'm going to make a separate model for the truss with pin connections to depict the dowels, what do you mean by the truss reactions get transferred manually to the beam? Or are you saying that I'll transfer them manually or if there is an option in the program to transfer loads to another model. Thanks.
RE: OVERLAPPING MEMBERS...NEED HELP
RE: OVERLAPPING MEMBERS...NEED HELP
RE: OVERLAPPING MEMBERS...NEED HELP
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: OVERLAPPING MEMBERS...NEED HELP
RE: OVERLAPPING MEMBERS...NEED HELP
RE: OVERLAPPING MEMBERS...NEED HELP
RE: OVERLAPPING MEMBERS...NEED HELP
Michael.
Timing has a lot to do with the outcome of a rain dance.
RE: OVERLAPPING MEMBERS...NEED HELP
The dowels, at 4'-6" OC, if they slip up and down within the concrete beam, and being welded to the truss, may be solely for lateral support of the bottom flange of the truss...
If the vertical deflection of the truss, however, exceeds the vertical slip capacity of the concrete beam connection, whatever it is, then a vertical load could be imparted to the concrete beam.
In all likelihood, at the 4'-6" spacing, a measurable degree of composite action may be a pipe dream. As mentioned, a good detail of the connection would answer a lot of questions.
I had previously envisioned these dowels as embedded in the concrete beam and welded to the truss.
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: OVERLAPPING MEMBERS...NEED HELP
'the truss is deflecting with the beam I can see from its behavior that it's acting as part of the beam. Well I think I just have to move it away...and revise their plans. Lots of work though',
it's obvious that you need the advice of an experienced supervisor.
Asking questions on a forum is not the best place to get that advice.
RE: OVERLAPPING MEMBERS...NEED HELP
I encountered some errors so I need to find a solution, that's why I'm hoping for some relevant technical answers so I can weigh, check and apply it to the problem accordingly. I'm very thankful to some members who shared their opinions relevant to the matter in hand.
Contrary to your opinion, I find forums very helpful, you can get lots of great ideas although, there are some irrelevant and unnecessary comments, but generally, seeking advice inside open forums is still one of the best way to find the answer/s that you're looking for.
One more thing, I don't think my experienced supervisor will be happy to help me with some part time jobs after my work in the office.
To the members who took some time to share their ideas addressing my queries, I'm very thankful to you guys. And to those who did otherwise, maybe next time you can at least just try to extend some help.
RE: OVERLAPPING MEMBERS...NEED HELP
I was just a bit concerned that you apparently contemplated changing the building plans because you couldn't model it in your analysis software. That's the tail wagging the dog.
I'm not trying to steer you away from using the forum, I've learnt a lot here and I'm sure you can too.
As for 'unnecessary comments'; they come with the territory, whether you appreciate them or not.
RE: OVERLAPPING MEMBERS...NEED HELP
Otherwise, determine the properties of the composite member and model it as a single member using these properties.
It sounds like you may be doing work outside of your expertise without supervision by a licensed structural engineer, which none of us here would recommend, and most place in the US prohibit.
RE: OVERLAPPING MEMBERS...NEED HELP
@TXStructural, Thanks. Just wanted to try the software, I want to learn more that's why I'm asking, if others are ashamed to ask because other people might think that they don't know anything, count me out. I will ask if something confuses me. I not only use all the brains that I have, but all that I can borrow. That is the reason why I'm here to learn from experts like you. Thanks again for the input I will look into it. As for now, I'll wait and see, all the documents and plans are with the building officials for approval. One more thing, nothing to worry, I have my own professional license and legally allowed by law to practice.
@Everyone, Thanks for all the valuable comments, you are my expert supervisors.