Nominal height of dome 1

[prashanth5723]

Hi.
Can somebody explain me how the nominal height of a geodesic dome is calculated? For a 17m dia tank, I noticed that the nominal height of the dome varies for two different dome suppliers, although both of them follow the standards of API 650G. API 650 G.6.2 tells that the maximum dome radius shall be 1.2 times the diameter of the tank & the minimum dome radius shall be 0.7 times the diameter of the tank unless otherwise specified by the Purchaser. Does this radius play any role in calculating the nominal height? pls suggest your ideas.

 

[JStephen]

I would assume that the manufacturers are free to choose a nominal radius anywhere in that range for their designs, and that if two different manufacturers use different radii, their overall dimensions will be different.
In addition, you may have some variation in detailing at the top of the shell and at the peak of the roof that affect the final dimension.
I would assume that the manufacturers try to use certain standard layouts in order to allow as many parts as possible to be duplicated from job to job.
Generally, I would expect the flattest roof to use the least skin material and the steepest roof to produce the lowest structural stresses, and the ideal configuration will be a compromise in between those two.