Tie Beams per Florida Building Code - Section 2121

[STR04]

In accordance with FBC Chapter 21‚ Section 2121 there is no allowance for masonry tie beam construction ("U"-block) for commercial construction. How is this handled if the architect wants to use split face cmu and doesn't like to see a concrete banding (conc. tie beam) around his perimeter?

TIA

 

[STR04]

but...if you're outside of Broward and Dade Counties for High Velocity Hurricane Zone does that pute you back to the prescriptive requirements of 2121.2 for Tie Beams? I guess they are saying in rural areas where a special inspector may not be avaliable or directed under an architect or engineer, use the more conservative concrete tie beam requirements. Does that make sense?

 

[ron9876]

The HVHZ is just another way to say South Florida Building Code and applies to Broward and Dade only so no the prescriptive method doesn't apply anywhere else. Don't know about inspection requirements in rural areas. West Palm Beach and Boca do require inspections.

 

[STR04]

your right. Section 2121 is HVHZ. Thanks for your help ron9876.

 

[Ron]

HVHZ is defined as Dade and Broward counties. A Special Inspector is required for reinforced masonry.

 

[concretemasonry]

Ron -

After reading my post, I recognize that what I said was not correct. I used the term "U" shaped bond beam, but was thinking about the open core, two way or "knockout" bond beam is rarely made in a knock-out fashion for obvious reasons. I was actually referring to the open core bond beam when I mentioned the performance in reinforced or partialy reinforced masonry because of the continuity of reinforcement. The traditional "U" shaped bond beam is entirely adequate for walls with relatively low lateral loads perpendicular to the walls. Obviously, for more sophisticated construction an open core bond beam is preferred. In some countries, they make open core bond beams with unequal heights on the face shells to permit cast in place slabs or precast to be used as a floor without changing the exterior coursing or appearance.

I think the reason for "dark ages" requirements in Florida goes back to the poor historically low level of construction quality, limited availability of appropriate or necessary CMU shapes and sizes carried in stock and lack of use of engineers in the typical "garden variety" structures in contrast to other regions of the U.S. and other countries. The lack of seismic requirements may also be a factor.

When I first got involved in the masonry construction (40 years ago) there was a minimum different CMUs available (10 or 20 different shapes/sizes) in Florida despite it being a very high use market. Last week when I was there, I saw very few improvements in the availability of improved shapes and interest in engineers in making real improvements by suggesting shapes that are available and used elsewhere. - The codes and applications of masonry has followed this stagnation. The contrast to states west of Florida is striking. I recently was in an area where there was an availability of over 500 different shapes (standard strength) available plus additional custom shapes (and strngths up to f'm of 3000 or 4500psi) available on special order with a very short lead time.

All of this has little to do with Florida codes and engineering, except to show that there are massive improvements possible.

Dick

 

[Ron]

Dick,
I agree. The Florida Building Code has been an ordeal for all of us. It will get there. It's a bit like the old sausage analogy...you might like the result, but you sure don't want to watch it being made.

Ron