I have a special concrete shear wall building with coupling beams (ACI 318-14). It's a 3 story low rise building made entirely out of shear walls. The gravity system is thick slabs (14") with stout beams and columns. My question is about when is a coupling beam a coupling beam. I have many...
I have a single story CMU building with a steel roof deck supported by steel joists. The building is in a high seismic zone (SDS=1.0). It's an industrial facility but it looks pretty similar to a strip mall building.
The architect has shown an alcove in the middle of the long walls (~100ft...
I'm investigating the buckling of a thin walled long tube that apparently buckled under torsion. The tube also had an external pressure on it, but that pressure was not large enough to buckle to tube. I can figure out the torsional buckling of the tube and the compression buckling of the tube...
I just noticed that CRSI now has design guides for individual subjects:
-Pile Caps
-Voided Slabs
-Cantilevered Retaining Walls
-Spread Footings
-Floor Vibration
Does anyone have any of these? Do they take the place of the CRSI Design Handbook? What year code are they based on? There isn't...
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Any thoughts?
I'm reviewing the design of a pressure vessel that uses a ring type gasket. The gasket is neoprene instead of metallic. There is a gasket groove on only one of the flange faces. The gasket seals against a flat face on the other side.
Does anyone know what a design like this might be based on?
I'm designing some flanges per Section VIII-Div 1 Appendix Y. I'm having some problems with my bolt stresses. I'm using B7 bolts and Section II Part D only gives you 23ksi allowable in Table 3 (20% of the minimum tensile strength). This thread has a similar question: thread292-251881 .
So...
This was a potentially very dangerous incident. Fortunately no one was hurt.
Link
What is the design load for walls like this. Was corrosion was the cause?
Is there a standard, somewhere, which says what should be included in structural calculations?
For instance, if I have a a deferred submittal where the calculations are done by the Contractor's engineer, what should I expect? I received a set of calculations that calculates all the loads for...
Just a quick survey:
1) Do you, in your typical concrete design, consider twisting moments?
2) Have you ever considered twisting moments?
3) If you do consider twisting moments, what method do you use for design (Wood-Armer?)?
4) What region are you in (USA, NZ, Europe...)?
I think that the...
I'm working on a project where the contractor would like to use ASTM A996 rebar in lieu of A615. I'm not familiar at all with A996. Are there any pluses/minuses between the two? Can A996 grade 60 be substituted straight for A615 grade 60? Why isn't A996 in greater use? Is there any real...
What is maximum height obstacle that you can have without requiring a set of stairs to step over it? For instance, a 6" curb doesn't need a set of stairs but a 3ft tall wall does. What about a 1ft tall wall? Is there an OSHA or IBC reference?
What are your thoughts on drop-in anchors?
I require that all concrete anchors have an ICC-ES report on my typical job. I don't know of any drop-in anchors that have an ICC-ES report (please tell me if you know of one). I'm guessing that drop-in anchors aren't as reliable as other anchor...
I'm recieving output data from a subcontractor who analyzed a structure using 4 node shell elements. They sent me a sketch of what they think are the local coordinate orientation with respect to the nodes (e.g. the local x direction points from node 1 to node 2) and the local stress output, but...
For those of you who are committee members for ACI, AISC, ASCE and the like, how much time to you spend on your committee work? How many get togethers do you have a year and do you have to travel to the meeting or is it an online meeting? I know it varies vastly by committee and organization...
I've been using an older concrete textbook on a project (Park & Paulay, 1975) because it has an in-depth review of obscure design issues (moment-curvature, corner reinforcing, etc...). It reads more like a summary of current research papers and concrete behavioral theories rather than just an...
Has anyone seen a good comparison between the different types of AWWA D110 tanks (Type 1, Type 2 and Type 3)? I'm specifically looking for comparisons on the long term performance of those tanks.
We typically specify Type 1 tanks. The Type 2 tanks are much cheaper, but I have to believe...
Where is engineering going? Down the tubes is the only place I can guess.
Some in the USA are trying to put the arts on par with engineering:
Oregonian STEAM Article
STEAM not STEM website
-So, should we water down our engineering education even further so we can be more artistic?
-Are...
Has anyone noticed that the 14th edition single shear plate tables have lower values than the 13th edition?
Example
13th edition: Table 10-9a, for 3-3/4" bolts in a 3/8" shear tab, the capacity is 47.7 kips
14th edition: Table 10-10a, for 3-3/4" bolts in a 3/8" shear tab, the capacity is 43.4...
I have an annular retaining ring that's holding in a spherical bearing. The spherical bearing has some side load that will get transferred into the retaining ring, so I'll need to design the ring to take that load. The specifics are a 7" OD, 6" ID retaining ring holding in a 6.5" OD spherical...
