6" CMU

[SteelPE]

I am working on a project where we have some interior not bearing masonry walls and an elevator shaft out of masonry. A GC was brought in to run the project and help the design team during the planning phase to help with budgeting the project. Somewhere behind my back a decision was made to switch these walls to 6" CMU. Now I'm not worried about the non load bearing walls but I am a little worried about the masonry shaft walls for the elevator. Are these blocks the same as the 8" blocks? Meaning:

I can get vertical reinforcing into them
We can obtain joint reinforcing (ladur reinforcing)
I can get bond beams into the walls
Keeping with masonry construction the dimension of the block would be 5 5/8" thick

In 17 years I have never been asked to use 6" CMU (maybe I am just sheltered here).

The issue is that all of the architectural drawings were switched to 6" CMU and the interior of the building is tight so a switch back is going to be meet the wrath of everyone above.

 

[Retrograde]

What is your normal lintel detail?

 

[hokie66]

Lintels in reinforced concrete masonry walls should be reinforced concrete masonry. If you don't like to do it that way, precast concrete lintels can be used, but the continuity is not as good.

 

[concretemasonry]

Retrograde -

The masonry units were tested and identified with markings (different color paint sprayed in the cores) for strength levels before the block were laid. There were actually 4 different strengths for each building in the complex that consisted of 5 structures and one was actually 22 stories and the remaining 4 were only 20 stories.

The buildings were designed in accordance with ACI 530. The exterior walls, corridor walls and party walls were loadbearing. Generally, masonry was partially reinforced. Interior unit walls were "wrinkled tin". Originally, the building was designed as reinforced concrete, but the time schedule was faster and cheaper for masonry. - The construction process was very similar to the Excalibur Hotel in Las Vegas except most of the floors slabs were cast in place and not cast on site.

Dick

Engineer and international traveler interested in construction techniques, problems and proper design.

 

[ahypek]

I've done plenty of 6" CMU buildings (shear wall) ranging from 2-4 stories in NYC.