HUD Blast Wall Mitigation

[stiffener]

I have a proposed HUD housing project that is to abut a property that has a 40,000 LPG above ground tank located on it. HUD requires that any building be a minimum of 750' away from the center of the tank and that common outside areas be 1,300' away. If it is impossible to maintain these distances, mitigation methods can be used. One option is a wall that will resist the pressure of the explosion. HUD doesn't have any guidelines as far as the load capacities for the wall in relation to the distance from the tank. Has anyone designed one of these walls before and what loading have you used? Thanks.

 

[Lutfi]

You will find out that walls are not going to be cheap nor practical depending how far you will set them away from the tank. I recommend the use of earth berms if possible. They work well NASA and many establishments use them for LOX, Hydrogen and other fuels. This way you can landscape them.

As far as computing the blast pressures there are several documents published by the DoD (department of defense) but I am not sure if they are available to the public. They base their blast pressures by equating the weight to equivalent TNT because most research has been developed around TNT. This is all I can tell you in this forum.

It is my advise to you is hire an engineer who is competent in performing these designs and let them do their magic. This will not make you less professional to your clients and it will produce results that are based on experience and good judgment.

Regards,



Lutfi

http://www.cdeco.com

 

[stiffener]

We have reviewed the idea of a berm but space is limited. We also do not know how high the berm would have to be due to a lack of infomation on the subject. I would have no problem having a specialist engineer design the wall. I would have no idea of where to find one though???

 

[SacreBleu]

Stiffener,
If the government does not allow access to the data you need, because Saddam Hussein had nearly invaded the USA, why not design a tapered, concrete blast wall, using "guesstimated" blast forces? If anyone challenges you to provide a more scientific estimate of blast forces, then challenge them to supply to you a source of that info.
Sorry for the sarcasm- I don't mean to offend anyone.

 

[jheidt2543]

A firm I used to work for had a client that built and tested fuel control equipment for the aircraft industry. They would perform tests on their equipment using high test aircraft fuels in what they called "Test Cells". The rooms were reinforced and grouted concrete block with precast concrete roofs, BUT they each had an explosion vent in the roof to vent any possible explosion gases. And, they did periodically have explosions in the Test Cells. The walls and ceilings survived!

Now, I realize your problem is quite different as far as the amount of fuel involved. But, you are out doors and bascially want the explosive force to go up, not out. So, while the force on the wall is high and may be subject to high temperature fires, it is actually not as bad as might be thought at first.

I have seen a number of seminars lately that purport to teach how to design blast resistant buildings. I also concure with Lutfi, there are government sites; DOD, FEMA and Homeland Security, that have information on them. Have you done a web search? If the information is not available on the web, try calling a government agency directly to see what information is available.

 

[bridgebuster]

Stiffener,

Try Weidlinger Associates or PB; they do work related to blasts.

 

[pba]

SacreBleu,

The reasons why you can't guess should be obvious - Don't engineer things which you don't understand.

Governments do try to keep the necessary information away from the public but it can be obtained by those who have a genuine need for it.

Stiffener - Do get a specialist to do the design. When you are shopping for a specialist, ask them what data they propose to use as the basis of their design.

 

[stiffener]

Thanks for the comments. I will most likely get a specialist engineer involved in the project. It's just frustrating when I you talk directly to the people at HUD and ask them the criteria that you have to meet based on their requirements and they just shrug their shoulders. I have tried doing web searches for information without any results. I am sure there is information out there on the goverment side but it doesn't seem readily available.