Brick Veneer - Seismic Mass
Brick Veneer - Seismic Mass
(OP)
I am working on a building with 2 stories of brick veneer (non-structural) bearing on foundation. In other words, the floors carry no brick load. I have been researching on internet and found mixed opinions in how the brick mass being considered in seismic base shear, here are some that I found:
1. Some engineers account the full mass of brick veneer in the seismic base shear calculation and distribute the base shear vertically based on tributary height of brick mass, i.e. floor-floor height x 40psf.
The reason is that the brick will produce additional seismic lateral shear from ground motion and distribute them thru brick ties to the main structure.
2. Some engineers do not account the mass of brick if the brick veneer is bearing on foundation directly.
I am hoping to hear some more opinions from you all and hope to draw a conclusion on this matter. If you know any code section that addresses this issue, please kindly post it on this thread.
1. Some engineers account the full mass of brick veneer in the seismic base shear calculation and distribute the base shear vertically based on tributary height of brick mass, i.e. floor-floor height x 40psf.
The reason is that the brick will produce additional seismic lateral shear from ground motion and distribute them thru brick ties to the main structure.
2. Some engineers do not account the mass of brick if the brick veneer is bearing on foundation directly.
I am hoping to hear some more opinions from you all and hope to draw a conclusion on this matter. If you know any code section that addresses this issue, please kindly post it on this thread.






RE: Brick Veneer - Seismic Mass
If you have to design for it - the forces are out of sight and the cost to contain it will skyrocket the price of the building. Plywood shear walls just usually won't work.
Remember - we just want the main parts of the building standing with few if any injuries to the occupants. We are not expecting it to look brand new.
The few California engineers I have talked to also agree.
RE: Brick Veneer - Seismic Mass
RE: Brick Veneer - Seismic Mass
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: Brick Veneer - Seismic Mass
The force at each level is per the vertical force distribution forumula in ASCE 7 (for US projects).
I don't see where you can suggest that the brick will be gone and then just discount it.
RE: Brick Veneer - Seismic Mass
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: Brick Veneer - Seismic Mass
I would think discounting it would be ill advised. If the brick would not be present during the second wave, might it not end up on top of someone who is outside?
RE: Brick Veneer - Seismic Mass
RE: Brick Veneer - Seismic Mass
Structural Design Engineer
New York, NY
RE: Brick Veneer - Seismic Mass
In my view if the kind of structure is not performing to satisfy what above, you modify both façade and structure itself to ensure the proper behaviour; that may mean including a reinforcement grid scheme within the wall itself, some kind of intelligent tie system to some competent structure behind, and enough of the structure enhanced to stand the brunt of the design seismic forces.