Blast load design

[hockchong]

Dear All,
I need some guide to design my vessel on blast load. My vessel is 26m ht and 3m ID with blast pressure 0.3bar @ 0.2 sec. My question is how to convert the explosion pressure 0.3bar to the force acting to the vessel.
Currently what I am doing is calculate as per wind calculation. I am too conservative or I have miss out some important calculation. Please help. Thank you.

 

[bvi]

Proper blast load analysis involves considering the dynamic response of the structure to the impulse load of the blast. Typically, this is based on simplified elastic-plastic dynamic analysis. Dyanmic material strength properties, which are higher than static, are also typically used. I believe you will probably find your approach to be very conservative.

 

[hockchong]

Thank you cb4 for you reply. I come across some calculation that using 3 times of the yield strength for the allowable stress. My question is, how to determine the allowable stress and if can, where can I find the references. Thanks again.

 

[bvi]

Here is a reference list

ASCE, Manuals of Engineering Practice, No. 42, Design of Structures to Resist Nuclear Weapons Effects, 1986.
J. M. Biggs, Introduction to Structural Dynamics, McGraw-Hill, Inc., 1964.
Center for Chemical Process Safety, AIChE, Guidelines for Design and Siting Criteria for Process Plant Buildings, New York.
Center for Chemical Process Safety, AIChE, Guidelines for Evaluating the Characteristics of Vapor Cloud Explosions, Flash Fires, and Bleves, New York, 1994.
Chemical Industries Association, Guideline, An Approach to the Categorization of Process Plant Hazards and Control Building Designs, London, 1979.
Chemical Manufacturing Association, Safety Guide, SG-22, Siting and Construction of New Control Houses for Chemical Manufacturing Plants, 1978.
Forbes, D. J., Design of Blast Resistant Buildings in Petroleum and Chemical Plants, Second Edition, John Wiley & Sons, 1982.
TM5-1300, Structures to Resist the Effects of Accidental Explosions, Department of Army, Navy and Air Force, Washington, D.C., 1990.
U.S. Army Armament Research and Development Center, Structures to Resist the Effects of Accidental Explosions, (6 volumes), 1990.
J. L. Woodward and P. Crossthwaite, “How to set explosion protection specifications for all process plant buildings,” Hydrocarbon Processing, November, 1995.
Benteftifa and Becht, Vapor-Cloud Explosions, Surviving, Encyclopedia of Chemical Processing and Design, Vol 61 Marcell Dekker, Inc., 1997 and also Hydrocarbon Processing, October 95 (Vol 74, No. 10)

 

[mayda]

Depending on how precise you want or need to be, you might inquire at the following company:

http://www.acescolumbus.com/

I understand that they have some expertise in blast and fragmentation analysis, using FEA techniques. Perhaps they would be able to anlayze your vessel. I expect they could give you a price quote, if you send them the pertinent information on your vessel.

 

[JWB46]

Reply is a bit late, cb4 has given all the best references, but you will find some useful software at

http://www.electronic-calculus.com

Hope this helps