Masonry as cladding 1

[papa2ten]

If exterior masonry wall is NOT being used as MWFRS,
should the wall be designed as cladding?

Thanks.

 

[redhead]

Definitely yes. The only question is what is the correct value for the contributory area.

 

[papa2ten]

If the wall spans vertically, the contributory area be 1'-0" X the height.

If the wall spans horizontally the contributory area be the length of the wall X the height of the wall.

 

[Lutfi]

Here is my input:

1. When you design the CMU wall for wind load perpendicular to it (windward and leeward) design it as component and cladding. Also, make sure you design it to the end zone pressure (ASCE 7 zone 5) even if the wall is within zone 4.

2. Design CMU wall for uplift from the roof, which should be determined on the basis of MWFRS.

3. Design CMU shear walls for MWFRS pressures. Do not include the internal pressure because it acts in multi-direction and it cancels out.

I like to recommend that you get a copy of "Guide to the use of the Wind Load Provisions of ASCE 7-98 by Kishor Mehta and Dale C. Perry. It is available form

http://www.asce.org

Good luck.