MAF Masonry knowledge base

Masonry Association of Florida, Inc. Florida Builds with BLOCK, BRICK & Stone.
  • News
  • Knowledge Base
  • FloridaMasonry.com

Missile Impact for 6" Masonry

10/16/2018

0 Comments

 

Can 6" masonry be used to satisfy the impact resistance criteria in Florida?

The FBC, 6th edition, Building, Section 1626.4.1 allows for 8" hollow masonry to meet the impact criteria for the HVHZ (Dade and Broward). Although there is no mention of 6" masonry 1626.4.4 allows for 2" of reinforced concrete to meet the requirements also.

Common sense would grant that solid grouted 6" masonry is going to perform better than 2" of poured concrete but again it is not mentioned directly.

That being said, FEMA P-320 Safe Room Const Plans specify 6" masonry with a #5 bar in a grouted cell at 16" o/c.

The more stringent FEMA P-361, Safe Rooms for Tornadoes and Hurricanes, 3rd Ed, March 2015 allows solid grouted 6" masonry with a #4 bar at 32" o/c.

As a side note, we plan to submit a code change to include solid grouted 6" masonry in the "deemed to comply" list under 1626.4 in the 7th Edition FBC. It is not currently listed simply because the issue of its use rarely comes up.
​
In summary, I can see no good reason why a building official would reject solid grouted 6" masonry as specified in P-361 as being acceptable for missile impact requirements in the HVHZ.

Links to additional information:

https://www.fema.gov/media-library-data/1467990808182-0272256cba8a35a4e8c35eeff53dd547/fema_p361_July2016_508.pdf

https://www.fema.gov/media-library-data/1418837502817-920f09bb8187ee15436712a3e82ce709/FEMA_P-320_2014-ConstructionPlans_508.pdf

0 Comments

How should intersecting masonry walls be fastened together in Broward and Dade County?

7/11/2018

0 Comments

 
The project engineer has requested that ALL intersecting walls be laid up with 50% of the units overlapping at the corner. There are MANY intersecting walls and this prevents any wall from being run in an economical way as you have to continually stop and build your lead for the intersecting wall. What does the code require?
An engineered masonry structure built in Dade or Broward is covered under the High Velocity Hurricane Zone section of the code, specifically section 2122. Section 2122.10 requires that "intersecting walls shall comply with TMS 402 section 5.1.1."

The referenced section gives three equivalent ways that intersections can be tied together. The first is that 50% of the units are overlapped at the corner. The second is that the wall shall be tied with a 28" long heavy steel "Z" anchor spaced at 48" vertically up the wall. The third method is to place a bond beam with .4 square inches of steel spaced at 48" vertically up the wall (you could use (2) #4 bars or (1) #6 bar).
​
Since the plans and specs did not call out specifically for the 50% overlapping, any of the three methods would meet the requirements of the job and the code.
0 Comments

Required Strength for Masonry for f'm=2500

4/18/2018

0 Comments

 
What strength do I need on my individual block to attain an f'm=2500 psi?
​Under the FBC-Building 5th Edition you required an individual block strength of 3750psi to attain an f'm=2500. Under the new 6th Edition Florida Code you only need a strength of 3250 psi. The change is in Table 2 in TMS 602-16. The strength of masonry was increased by about 35% from the TMS 602-11 which was the Masonry Standard referenced in the 5th Ed FBC-Building.
Links to additional information:
​

​https://test2.floridabuilding.org/bc/bc_default.aspx
0 Comments

    Authors:

    Picture
    Don Beers, PE, GC
    561-310-9902
    don@floridamasonry.com
    Picture
    Jerry Painter, FASTM
    352-378-7511
    painterjm@gmail.com 

    Categories

    All
    Backer Rod
    Bar Hooks
    Block Strength
    Bond Beam
    Brick
    Cell Size
    Cell Width
    Code Requirements
    Concrete Block
    Control Joint
    Control Joints
    Corner Attachments
    Cracking
    Crosswebs
    Design Criteria
    Envelope Leakage
    FBC
    Filling Cells
    Fine Aggregate Grout
    Florida Building Code
    F''m
    Grouted Beam
    Grout Height
    Grouting
    Grouting Of Block Walls
    High-strength Masonry
    Horizontal Steel Spacing
    Integral Waterproofing
    Intersecting Walls
    Job Requirements
    Jobsite
    Masonry Details
    Masonry Websites
    Max Bar Size
    Missile Impact
    Mortar
    Net Area Strength
    Rebar
    Reinforcement
    Safety
    Shrinkage
    Slip Joints
    Sound Insulation
    Sound Transmission
    Stucco
    Stucco Bonding
    Stucco Over Lath
    Table 2
    Tie Beams
    Vertical Steel
    Videos
    Wall Design
    Water Intrusion

    Archives

    February 2019
    January 2019
    December 2018
    October 2018
    September 2018
    August 2018
    July 2018
    June 2018
    May 2018
    April 2018
    March 2018

    RSS Feed

Masonry Resources

Clay Brick Masonry
Concrete Masonry
Mortar & Grout
Reinforcing Steel
Sustainability & LEED
Wall System Comparisons


MAF Websites

​Find out more about Masonry
​Pre-Apprentice Programs by visiting:
www.MasonryEducation.org
Picture
Masonry Association of Florida, Inc. |PO Box 24474 , Fort Lauderdale, FL 33307
Copyright  ©  2017. All Rights Reserved.
Sitemap
  • News
  • Knowledge Base
  • FloridaMasonry.com