Masonry Magazine September 2004 Page. 35
In 2001, the Standard Practice for Bracing Masonry Walls was updated. In the update, all of the tables were adjusted to modular values, and design tables, which change the heights of unbraced masonry above bracing as the wind speed changes, were added to the Appendix.
In 2003, the MCAA published the Masonry Wallbracing Handbook. This handbook contains over 700 different configurations of masonry walls, including openings. While it is based off of the Standard Practice, it is a step-by-step pictorial of where wall bracing should be placed (see Figure B). The MCAA is currently working to develop wall bracing software, which is scheduled for completion by early 2005.
Conclusion
THE COUNCIL FOR Masonry Wall bracing recognizes that it is impossible to prevent the collapse of a masonry wall during construction and that life safety is the primary concern. The Standard Practice and the Masonry Wallbracing Handbook have developed a procedure whereby the wall and area around the wall is evacuated at a prescribed wind speed. While the insurance companies may not agree with this approach, it reaches the goal of preserving the safety of all workers around a masonry job site. This means that, if a wall falls inside of the limited access zone after it was evacuated, the wall bracing was adequate... Adequate enough to make sure that no workers were injured or close to being injured.
Rashod R. Johnson is the Director of Engineering for the Mason Contractors Association of America. He is the incoming Chair of the Council for Masonry Wall Bracing and co-editor of the Masonry Wall Bracing Design Handbook. For more information, he can be reached at rjohnson@masoncontractors.org.
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September 2004
Masonry
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