CMU Blast wall design for HUD Construction 1

[keen_mentee]

I am working on a Department of Housing and Urban Development (HUD)project where I need to design a 6 ft high concrete masonry unit (CMU) blast walls. The requirement of the blast wall (and its material) is as follows, "Thermal heat flux exposure threshold of 450 BTU/hr/ft2 for people in open spaces where people congregate, such as parks and playgrounds and blast overpressure threshold of 0.5 psi as the maximum allowable pressure that can be measured at a distance from an explosive hazard applicable to outdoor unprotected facilities." I designed a cantilever cmu wall for the 0.5 psi (=72psf) and got a solid grouted 8-inch CMU wall with #4 rebars @16 inch O.C. vertical rebars to work for 72 psf pressure. This does not seem like a strong wall so I am not sure if there is more to the loading that I am missing. I would like the expertise of the community on this and also what I could do for the 450 BUT/hr/ft2 requirement. Any relevant information and design examples would be greatly appreciated.
#learningalittleeveryday

Thank you.

 

[bones206]

I would say partially grouted reinforced CMU is still susceptible to shrapnel, but yes fully grouted CMU much less susceptible.

I found that a brick veneer with fully grouted CMU cavity wall system has a surprisingly high level of ductility and energy absorbing ability. The mass of the brick and the ductility in the brick ties are beneficial.

 

[bones206]

This is a pretty comprehensive test report for partially grouted walls:

https://apps.dtic.mil/sti/tr/pdf/ADA555022.pdf