There may be something to this. The stairwell this is in does get cold in the winter. I don't think they have heating in the stairwell and the wall in the picture is an exterior wall.
I'm not yet convinced its not a buckle knowing the location is protected by the nearby stairway. If its due...
Thanks... If its not wise to take out the column, I would for sure want to replace it since it seems like it is also twisted slightly. I'm pretty sure the "buckle" isn't impact damage since its in a stairwell underneath a flight of stairs at a location that isn't accessible to anything that...
A client of ours has a 2-story manufacturing facility that is primarily precast concrete construction. We noticed an unusual cracking pattern in one of their precast beams that is exposed in a stairwell. Analysis of the beam and design of a fix are out of scope at this time, but we want to do...
steveh49 - Thats good advice... Luckily this a contractor we have a long-standing and good relationship with, which makes things like this so much easier to deal with. We will likely split the cost of the repair (which isn't a large cost by any means).
They're able to install the dowels as...
SlideRuleEra - Its 12" thick with #6@12" each way & each face... I'm proposing to add in dowels of the same size and spacing with an additional dowel lined up just outside the edge of the manway above.
retired13 - correct... not cantilevered since it does have a roof bracing the top of the wall... I agree that its not a big problem for the tank as a whole as its a small section of the tank wall, but I'd expect extensive cracking locally in the area when the tank is re-filled (without any...
JAE - the manway has an embedded steel frame around it... There are no nearby out-of-plane concrete walls. The flexural stresses in this area are almost exclusively in the vertical direction (stressing the inside layer of reinforcing)
Miningman - That is indeed part of the problem... they were not given clear drawings showing what was expected, so we are also partly to blame (which complicates things a bit). However, neither myself or any of our structural engineers were made aware of this project until after this hole was cut.
We have a project with an existing rectangular concrete tank that has a stainless steel lining (so concrete is not critical for tank being water-tight) and we needed to install a 6" pipe through the tank wall. We expected the contractor to core a small hole just above the tank floor through the...
Good point with the ASME code and a duct running hot. This duct runs around 150 to 170 degrees F. I'll look into the B&PV code and the SMACNA standard.
Thanks, for the responses!
I just had a thought... Since I'm not that far outside the D/t limit in AISC F8, I could assume the steel is a lower yield strength than it actually is in order to force the limit to be met. I would think this would be a conservative way to analyze the duct if the difference is small... do you...
...a bit of a roadblock since AISC (chapter F8 in 13th edition) limits the scope of the chapter to round HSS sections that have a D/t of less than 0.45*E/Fy, which this duct is slightly over even before accounting for section loss (384 vs 363). The duct is primarily subject to bending forces...
Thanks everyone once again for the advice. In case anyone is interested, further testing has revealed that at the base of each pop-out was found a piece of andesitic tuff course aggregate which are very absorbtive.
CVG - That will definitely be an option presented to the client, but I want that to be the client's call, because it would probably lead to pretty severe push-back from the contractor if we ask them to rip it all out. I'm planning on taking the position that I'm only going to lay out the...
Thanks for the responses... the hangup I have with chipping out each of the pop-outs is the shear amount of labor that would be involved. There are two tanks that are affected with each one being about 115' in diameter, and these pop-outs are roughly spaced two or three feet apart on average...
Double integration would work well as mentioned. Personally, if I wanted to verify it by hand, I would put together a simple Excel spreadsheet to superimpose the deflection equations for each of the three point loads. I would use AISC Beam Equation #8 to calculate the deflection at regular...
I have a unique situation that came up in the last week, that I'd appreciate some opinions on.
We have a wastewater tank that has bolted steel glass lined walls with a concrete floor. The slab was poured about a year ago, and there are several concrete spalls 1"-2" in diameter dispersed...
