A radius of 32 and a height of only ~16.2 is not a hemisphere. If the beams form a true arc above the vertical portion then there is math somewhere to figure out the area of 16.2m of a 32m radius sphere.

https://en.wikipedia.org/wiki/Spherical_cap: If the radius of the base of the cap is , and the height of the cap is , then the volume of the spherical cap is[1]

and the curved surface area of the spherical cap is[1]


I get 3257.2M^2

add the vertical area = circumference * 1.8 = 362M^2

Do you get 3619M^2 total surface area?