I honestly do not have much to base my opinion off of besides more recent structural literature that discusses iterative approaches such as this one:
https://www.structuremag.org/?p=10924
With discussions in our community regarding 'iterative' processes along with the development of structural...
I am using RAM Structural system. I believe that this software is commonly used in our industry and was hoping to get input on how others typically approach the 'iterative' portion of their design with similar software. Having (2) models, one with cracked walls and the second model with...
Hi all, I wanted to inquire about how some of you perform your iterative design process for concrete shear wall crack factors and also discuss my current methodology. I am hopeful that I may be able to create a more efficient process and try to hone down on what may be considered more of a...
Hi all! Hope everyone had a great Christmas and is ready to get back to the grind!
I have a situation in which I would like to get some input from you forumers. I have an HSS beam that must tie into a girder and then follow with an overhang. Due to height restrictions I cannot afford to...
@KootK, again I must disagree, "LTB has nothing to do with flange buckling"?
Then why do we consider the radius of gyration of the flanges when considering strength w.r.t. LTB? I feel like with the advent of the 13th and 14th AISC editions & imperial design we may have strayed a little too far...
@Kootk
I disagree with your last post 100%. AISC has stated previously that there is a difference between bracing of flanges. There are even well known distances from either flange that a member shall fall within to be consider bracing that flange for LTB. Sure some people will consider both...
I appreciate the quick responses and tend to agree with what both of you are saying. Would you also treat the example of a continuous beam with pinned supports the same way?
Imagine a beam with infinty length and with pinned supports to the bottom flange at every 10'. The bottom flange...
Alright Ladies and Gents,
I've looked through just about all the old unbraced length threads and yet I still feel someone unsatisfied. I was hoping that I could get some opinions from some of the people here on this board. I am also familiar with what AISC says on inflection points as well as...
Hello all,
Lately I have been working on a project involving retrofitting an existing structure where more weight would need to be added to the original system. Our retrofit puts us in the category of an Alteration 2 within the IEBC code. After investigation of this older structure it has...
Hello all,
I am checking some old deep web girders for additional loads. I am familiar with AISC 13th Ed. Eq's J10-2, J10-3 for Web Local Yielding and the other local web limit states and know that these equations are used for concentrated loads coming from bearing situations (can occur at...
Cliff,
That was my original point of thinking, the point load will create more of a "beam shear" rather than distribute its way around the column and thus I wanted to send the load directly to the existing columns through some kind of mechanism. I guess the concern was if I am within the "d"...
Good Morning All!
I've looked over the forums and have found some topics regarding one-way shear in a two way slab system however none cover the issue that I am currently facing. At my office we are currently having a debate among the structural engineers and was hoping I could get some more...
AISC 7-13. For this type of connection it is typical to put a pipe or sleeve in between the walls of the HSS to prevent flexing of the HSS walls. This should alleviate concerns about bolt bending, however this might not be necessary provided you do a local check on the bolt :)
Thanks all for your help, definitely got the ball rolling on some avenues of thought. However bizarre the connection may be, by AISC standards through bolting is permitted in shear connections if the connections does not require a fully tensioned installation (aka slip critical). It's for this...
Hello all,
I am currently reviewing connections for a fabricator and have a unique connection that I have never run into before. Although I have some avenues of thought of how to analyze this connection I want to see what others think are the controlling local issues that should be...
Desertfox, I appreciate the links, the second one is a good summary for anyone who is designing lifting lugs and I have followed the procedure on several lifting beams in the past.
dhengr, I understand what you are saying, however I am limited in my materials to an I-beam as the client has...
Here is a very quick sketch up done in MS_paint of the scenariohttp://files.engineering.com/getfile.aspx?folder=3c0ce348-a47e-4559-8e5d-1c1c7dc3e65b&file=lifting_beam_sketch.jpg
Hi all,
I have a question regarding a local check that I need to perform for a spreader beam. For this given application the lifting points on the beam are directly over the loading points, so in theory this means no shear is in the member , rather there is tension flowing through the web of...
AISC has a guide on how to design and construct lifting beams written by David T. Ricker written in 1991. In it he goes over a very general method for designing spreader beams (one that doesn't even mention axial forces...) for an I-beam section. Using the guide hand in hand with the AISC...
Come to think of it, tell me if this explains it:
I have analyzed the HSS square spreader beam and let's say it has a flexural capacity of 5 kip-ft. This is simply a global check on the beam, so sure it can handle 5 kip-ft globally, but looking at local checks on the beam if the lug plate is...
