Aluminium Self Supported Geodesic Domed Roofs 1

[Hotwheels1]

Hi Fellow Engineers

We are in process of specifying tank roofs for client for two tank of diameters.
D1 = 30.8m
D2 = 15.1m

Storage medium are a combination of gasoil, gasoline (with IFRs) and baseoil.

We are aware of the various advantages vs disadvantages of the self supported aluminium geodesic dome roofs, however, we are trying to justify in terms of cost whether the geodesic dome roofs are feasible for a tank of 15.1m in diameter.

Is there a rule of thumb or hand calculation at which diameter it is better to specify cone roof tanks?

Regards

 

[HTURKAK]

In past, i compared the cost of aluminum dome roof vs steel dome. The material cost aluminum is about 5 times of carbon steel in my region. My findings was , aluminium dome roof was economical after Diameter D>40 meters.

However, you may run calculations to see the cost difference. If you wish to compare, i would like to remind the necessity of tension ring for Alu. dome roof and the necessity of designing the tank for open top ( wind girder.. ) , the future maintenance and paint cost , erection simplicity....

To my beat knowledge , Aluminium roof is only constructed as geodesic dome roof while , for CS, the alternatives for fixed roof (cone roof, umbrella roof, dome roof, and with rafters, center supported,.......)


My suggestion will be for D1 = 30.8m Cone roof with radial internal trusses and for D2 = 15.1m Cone roof with radial rafters .

If you make a comparison , and share your findings with us ,i will be happy.

 

[LittleInch]

These guys, who actually fit them so are probably on the side of the AL roof seem to show that 30 odd m is about the start of breakeven.

https://www.easyfairs.com/uploads/tx_ef/VACONODOME_2014.pdf

This article seems to cove rit well

https://webcache.googleusercontent....for-fixedroof-tanks+&cd=1&hl=en&ct=clnk&gl=uk

Or " Without considering other initial and long-term cost factors (listed below), the aluminum dome usually becomes cost effective for tank diameters of 40 m or more, the diameter for which multiple rings of columns would be required for an SCR. The aluminum-dome roof is cost effective for tanks larger than 20 m when compared to a steel-dome roof and larger than 10 m if internal coatings are needed for steel."

Other factors are if this is a retrofit or new tank roof. Retrofit - any size is better, new build.

You might have been better asking this ins the storage tank forum....

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[HTURKAK]

Dear LI, Is this quote from O&G J which you have provided the link? I could not see may be for membership requirement. I will not agree with .
I think comparison of ADR with Steel Dome roof is not fair. If this is the case someone may ask , comparison of Steel cone roof VS alu. cone roof.