As the previous thread was locked, I felt this was a subject of interest and am continuing it, without insulting anyone. I am not an expert in grain bin/silo construction, but having been a farmer during my childhood and having worked on them, I feel I do know something about them.
Gale and Josh, there are numerous types of grain bins/silos. The most popular at this time is the corrugated galvenized units, due to manufactured pieces and simplicity of erection. This type of unit can be easily repaired when the roof is damaged, as most of them bolt from the outside wall, unlike the concrete bin/silo. This does, however, require that there be access from the interior of the bin/silo. for the panel security bolts to be installed. It is preferable to have the bin/silo empty at the time of repair to the roof. Many people have lost their lives in bins/silos that contained product, due to suffocation when engulfed in the grain.
There is a jump form and a slip form bin/silo. I worked for Riceland Foods many years ago, while in college. During the summer months, when the slip form grain dryers are usually built, I pushed a concrete buggy for a while and then was made concrete foreman. My first cousin was project manager and taught me a lot about construction of these very large grain bins/silos. The slip form is a constant poured concrete unit and is run 24 hours per day until the pour is complete. Lift jacks were in place and as the concrete was poured, the jacks were raised. These types of slip form units typically have a solid concrete deck, not a pitched cylindrical roof. Venting is usually on the top deck. Air is drawn through roof vents by a very large suction fan(s) to assist in drying the grain.
The jump form bin/silo, is usually a 4' pour using 4' forms and when dry, the form were stacked on the recent pour and another pour made. This is done with external and internal scaffolding. A sloped roof or flat roof can be installed. Access to the roof panels would be from the inside and outside.
There was an old design of in place concrete pre-stressed slabs that was built, which require the use of hoop tensioner cables. This was required to give wall strength due to bulging when the tanks were full.
No structure, to my knowledge, has to be brought down so the roof can be repaired. This can be accomplish with external and internal scaffolding or man lifts. Some of the older bins/silos, after a period of time have become dangerous, due to bulging pressures and the owner not performing yearly maintenance on the tensioner hoops.
Gale, this is a specialy item and probably should not be in anyones database. I understand you were trying to help someone with a problem and question. That is commendable, in my opinion. I could not foresee calling anyone at Integraclaim and them assisting me, if I had the same question. Thanks for caring enough to want to help someone.
Success is not final, failure is not fatal: it is the courage to continue that counts.