Found much interesting comments and discussions on X. Getting to be my go to source - but still being careful. Center core column structure and flat slab construction. Similar to construction in the 60's that I am familiar with.
Viewed a very long apparently government report yesterday on Youtube. Cannot find it today. Very critical of the situation. Apparently AI composed as I have never seen such a complete report this soon. I searched YouTube and Perplexity for the report; maybe there are better sources some...
The latest ASCE 113 Substation Design Practice Manual has a chapter on different kinds of protection walls for collateral damage from explosions. Also most current transformers are designed for the cover to explode upward before the side wall panels.
Bingo. Old substation (transformer?) and 106.2 percent of capacity! That's a sign for extreme degradation of the coil winding insulation and is discussed (WARNED) in a number of IEEE Transformer publications. There may have been a short circuit that was the final straw.
Initial question: How old was the transformer? Did the coil windings have a permanent compression system? A few years ago there was a 30 year old transformer that burned at a Houston substation. Transformers do not run forever and there should be a remove from service plan in place. These...
And the anchor bolts have to account for the thermal expansion of the ring plate. So the holes have be larger and the connection of the bolt some where above the ring base plate. If the bolts have to resist uplift, we usually will add in a small P-delta moment/S to the tension force of Pt/A.
If it is a core clamping issue or a windings clamping issue, do you know if the clamping system on the windings has some sort of a hydraulic compression system? The coil stack column may have shrunk due to degradation and now is loose. Helpful if we know the age of the transformer and whether...
When the electrical engineer designs the transformer coil windings assembly, the physical design is for the wind assembly not to fly apart when a fault goes through the system. For axial loadings of the assembly, he provides a force value that the tie rods must resist - say 300,000 lbs. This...
Raj6:
I am the EOR on a number of tall flagpoles.
https://en.wikipedia.org/wiki/Aqaba_Flagpole
Your latest summary of the criteria required for the design is very good and is what I used on my “monster” poles as these flagpoles were initially called. Today the highest flag pole is the Cairo...
Once before I said some of these things - but my introduction to big numbers for multiplication and division was a about a 3" thick logarithm book that required looking up large numbers and just adding them together and then getting the result from consulting the book. (1961) Remember putting...
IEEE 693 concerns the seismic design of substations including transformers. The California PUC requires that transformers are able to operate during an earthquake and continue operation. The document does not consider degradation of the insulation and what condition the insulation is when the...
Could you hold the approval until the special solution is provided to you for approval as per the contract? I have had the concrete trucks sent away because the geotech and I were having an argument. Can get messy.
Dik: That's the point. What is the maximum variation? The coefficient of expansion of concrete and steel are different and the concrete value is probably not what is in the back of the steel manual. Take the maximum differences in the maximum possible coefficient of expansion of concrete and...
Should also check the thermal stresses. Might have to let one end slide and the other end be an anchor. The COTE of the concrete is unknown because you probably don't know which quarry the aggregate came from. This is currently a contentious discussion concerning transformers and their...
We started with Visacalc. It ran on a Radio Shack Model II. Later we moved over to Lotus 123. Have many files in WK1. Can open with Excel and Libre and save to Excel. The macros don't work. Have about 200 templates, many that were "production" templates, that is they would do 7 problems per...
Just sister on each side without going to the support. Make sure you have enough fasteners to transfer the end shear to the original joist and check the main joist for adequate shear capacity.
It depends where in the country the cable tray is. Does your contract provide a thickness? I've worked with ice from 1/2" to 5". Had one project in North Dakota where the BR said 1/2" and the local building department said 3". I used the 3" and was chastised by the BR plan checker. But I...
