Thanks for your responses guys. I did receive a response from MBMA and they provided me a copy of a document, "Retrofitting/Reinforcing Metal Building Systems." It basically states that the transition to 50 ksi steel started in the 1960's and was for the most part complete by the 1980's...
In speaking with my colleagues here locally, it was understood that the prefab industry had been using 50 ksi steel as early as the 1970's. I was hoping to see if there was some historical information as to the steel used for those building designs. I have sent the question to MMBA but have...
I agree with the advice of just chalking this up to a business loss. On a side note, not sure how or if this applies, but a method we used to collect was to inform the building department of removal of our seal from the drawings. Basically, we contacted the building officials in our area to...
For your circled condition, we have seen this condition previously. Our solution was to provide a double angle connector at the end of the cantilever beam attached to the beam with through bolts. The "flange" legs of the angles would be flush to the inside face of the rim beam with a steel...
I am involved in verifying the structure of an existing prefab metal building. The building was originally designed as cover structure with open walls. At some point following, walls were added and there appeared to be no retro-fit of the existing frames. For my analysis, I have hit a bump in...
You could cantilever a thickened slab or create beams at some spacing within the slab to allow the foundation to be pulled back from the wall. I would assume that the portion of the CMU wall from the slab up would need to remain as located. The wall would be supported on the beam element at...
I am currently designing a water tank per ACI 549.1R. The one question I have is what is the significance of the Specific Surface of Reinforcement (Sr) criteria?
In going through the design, I have been able to meet the cracking criteria and the Volume Fraction of Reinforcement (Vf)...
I agree with Lion06....Make your splices lap over the support, assuming of course, that this is a horizontal deck and the loadings are typical in that you have negative moments over the supports and positive moment at the bottom of your slab.
Isn't the 30 foot limit for an unbraced height of 30 feet? Since you have floors at 13'-4", tie the veneer back to the floor diaphragm at each of those levels. And at least one or each of the floors, provide a shelf angle to "break" the veneer and reduce the impact of wood shrinkage.
I understand what you are saying about the shear friction. Without researching the exact particulars of the code reference for shear friction (Deadlines this week..lol), it would seem that the shear friction issue would need to be considered where shear reinforcing is required for the shear...
No...There no extraneous conditions for the concrete that would require a deeper embedment. The top mat of the footing/slab was detailed to have a 2" cover. The detail sketch I had provided was an as-built of the field conditions as relayed by the client and photographs of the rebar and formwork.
I agree with you all that the condition is a very poor condition. Like I said earlier, the bars were tied by the contractor to the top mat of steel, and I was not given the opportunity to review the shop drawings or inspect the rebar prior to the pour. It was not detailed to tie into the top...
Hokie...That is argument I am making for this condition...Like I said, it was a condition that was placed by the contractor and was unfortunately not brought to light until after the concrete was poured.
Granted...IF the bar ever went into a tension condition, then I would agree with you. However, the condition, during the life of the vault, is that it will be under a constant soil pressure. Even should a condition occur where only one side of the vault is fully exposed, the side walls would...
Yes, these are wall verticals and at the bottom. Attached is a sketch I issued on the project.http://files.engineering.com/getfile.aspx?folder=cfb589a8-b19b-4223-8f54-f969be052d68&file=embedment.pdf
I have a project in which I have designed a concrete vault, completely underground. The walls were designed using a "fixed-end" beam analogy. Therefore, at the support ends of the wall, we have a negative moment where the inside face of the concrete is in the compression region of the beam...
Back to your first question about the instability issue...For RISA 3-D, I rarely use the "pinned" boundary condition when you are creating a model that could be analyzed as a 2-D model, i.e. a single beam span in one direction. With the 2-D model, it is always assumed that your member(s) are...
I would recommend against adding the mid-span support.
There are couple of write-ups available that discuss the strengthening of bar joists. Unfortunately, I do not have the information to list here, but I do remember finding them through a search of the internet. A typical strengthening case...
