Hi All,
Structural Engineer here. Every so often I need a thickness measurement on existing structural steel (carbon steel). I have access to a Olympus 45MG, but it only has a 303 SS reference block.
I am usually measuring material that is .1" to 1" thick and I would like to be within a few...
You may want to check out this article from Structure Magazine on the topic.
https://www.structuremag.org/wp-content/uploads/2014/08/C-StructuralPractices-Iqbal-Oct081.pdf
In single story pre-engineered metal buidlings, you sometimes see a stacked X-brace with tension rods. This would look like a two story X-brace systems, but in a single story building. Where the two levels of X-bracing come together, you effectively have a K-brace condition, except there is a...
Thanks for your responses.
IFRs - you are right, when I run the #s, I get a 1/4" pl at dome and 3/8" at cone (assuming a 4.5:12 slope which produces similar total roof height). A cone may be more economical.
JStephen - in the API 650 Roof Definitions - it says 'A self-supporting dome roof is a...
I have a 40' diameter atmospheric tank designed per API 650. The roof needs to be self supported, so I am anticipating a dome roof. I am owners rep and will be specing the tank and assisting in the owner in purchasing and construction.
I am unclear on how these are typically built. To make a...
Looks like an arch. Better make sure you either account for lateral kickout forces at the top of your bearing wall or detail to not allow these forces to develop. And make sure that you are on the same page with the truss mfr on lateral deflections/forces at bearing wall.
bookowski - are you confusing Avc with Avco? Avc is calculated based on geometry of actual condition. Fig RD.6.2.1(b) is reflecting Avc calculation. Avco is an idealized condition for a single anchor - this term will end up in the denominator of equation D-31.
In thread809-180411, the OP asked for a reference guide for Re-pad design at the anchor chair - I am looking for the same. I see that in some software, the shell stresses are checked with the combined thickness of shell and re-pad. This seems potentially un-conservative. What might be more...
Thanks for the response. When you say to "noted on the name plate", is this done by "API 650 (Modified)" or is there a better way. Thanks for your input.
I have seen many tanks with a planar sloped bottom (aka shovel bottom) and a drain at the low point of the slope. This drain might be a 6" pipe vertically centered on the wall to bottom plate joint and then run in to the tank a few feet (I have attached at detail from an existing tank). The...
JStephen, thank you for your response - it is very helpful. Thicknesses given are all wall thicknesses. Shell is welded. I am currently using the lowest API 650 SS stress values and a joint efficiency of 0.7. The tank has already been moved from one industrial plant to another and is currently...
I am a Structural Engineer doing foundation and anchorage design for the relocation of an existing tank. The existing tank is 14' dia x 44' tall. Material is unknown SS and wall thicknesses are 0.140", 0.109" and 0.078" from top to bottom. The thicknesses are very consistant, so I don't think...
I am specifying a tank for 93% sulfuric acid following NACE SP0294-2006. The document recommends using carbon steel for the tank but appears to be recommending stainless steel for the nozzles. Is this normal? It seems like there would be a corrosion problem at interface of the stainless and...
I am specifying a tank for 93% sulfuric acid following NACE SP0294-2006. The document recommends using carbon steel for the tank but appears to be recommending stainless steel for the nozzles. Is this normal? It seems like there would be a corrosion problem at interface of the stainless and...
