Cavity filled double leaf brick wall - Capacity in bending and shear 1

[LR11]

Has anyone come across a referee for the following:
- Capacity of a double leaf clay brick wall, with reinforced concrete fill in between.

I can approximate but was wondering if there was a refined method.

 

[r13]

I am not aware of any literature available. I think you need to use mechanical device to make it a composite wall.

 

[dhengr]

LR11:
From the U.S., try the “Tech Notes, on Brick Construction,” by Brick Industry Association. They have a whole list of Tech Notes on the various aspects of structural design with brick. Most of the Bldg. Codes have sections on Brick Masonry construction. You should be able to find most of this on the internet.

 

[LR11]

OK thanks for responding. The Tech Notes seem to be a good resource. The concept was discussed in No. 45 but not quantified.

 

[dhengr]

LR11:
Look in the Tech Notes #ed 17, “Reinforced Brick Masonry,” etc, etc. Essentially, you pick an f’m, as a function of the brick, mortar and grout you are using, and then everything is pretty much std. reinforced masonry design, and engineering common sense. It’s essentially Reinforced Conc. design, with a twist to account for the masonry units acting slightly differently the poured conc. Some codes have some tabulated min. f’m values you can use in an almost prescriptive fashion for a given masonry unit and mortar type; alternatively, you test a number of samples with your brick, mortar, and grout to establish f’m, then spec. a min. strength brick. You could usually use a higher f’m if you required special inspection and some special details too. You show a fairly std. detail for that wall/slab, conc. blk. for the inside wythe would probably be cheaper than your brick. Note, many of us use the term masonry ‘wythes’ in place of your ‘leaf,’ which grow on trees. I haven’t really studied or used the last few eds. of the various codes and stds., so it’s for you to ferret out the details and latest variations on our older simplified design and construction methods. But, I do have a few 12&14 story reinforced masonry bearing wall bldgs. which are still standing and haven’t had any problems that I know of. They did not involve EQ design criteria.

Edit: And, in fact, you would do well to make the first course or two of the outside wythe out of conc. blk. too. Clay brick does not generally do well near or below grade. It is susceptible to damage and deterioration when it can be continuously wetted.

 

[LR11]

Thanks for the detailed explanation dhengr. It appears the method is more common than I was aware of. I will look at replacing the internal leaf or wythe.