Sep 21 2005
Masonry structures built to comply with current building codes performed well in the face of Hurricane Katrina according to the preliminary assessment of a disaster investigation team sponsored by The Masonry Society (TMS).
Arriving in Mississippi three days after Hurricane Katrina struck, the team observed intact, partially damaged, and demolished structures at sites in Pascagoula, Biloxi, Gulfport and other Mississippi coastal towns.
"There is a vast improvement in the performance of structures built in the past 10 years compared to structures designed according to older codes," says NCMA's Jason Thompson, structural engineer.
Thompson added, "Intact masonry structures throughout the affected coastal region exhibited wind resistance characteristics that are expected from structures designed and constructed according to the International Building Code (IBC) and International Residential Code (IRC)."
Prominent instances of concrete masonry walls withstanding the hurricane forces were noted at a Gulfport Kmart and Biloxi Wal-Mart store, plus a Harrison County building very near the Biloxi shoreline. Images of those and other projects are posted at http://www.ncma.org/Katrina, or linked at http://www.masonrysociety.org.
Thompson notes that with the introduction of the IBC, design and detailing requirements for structures located in hurricane-prone regions of the country have increased substantially compared to legacy building codes. Yet, while the understanding of naturally occurring events such as hurricanes and earthquakes continues to expand, there are countless variables with each event that cannot be accurately predicted.
"We must keep in mind that building codes only stipulate minimum requirements for health and safety."
Combined with our less-than-complete understanding of these natural events, savvy homeowners immediately recognize the benefits of building with durable, structurally redundant construction materials such as concrete masonry. Assisting the TMS team were representatives of Birmingham, Ala.-based Block USA, the Southeast's second largest concrete masonry producer and supplier of much of the gray and architectural block in coastal Mississippi.
Leading the team was the University of Louisville's Terence Weigel, Ph.D., who notes, "When catastrophic events like hurricanes damage structures, it is important to conduct an investigation as quickly as possible before clean-up efforts are begun to collect forensic data and determine how well the structures performed. Quick-response field studies conducted following major disasters are vital to identify knowledge gaps where further research and building code revisions are most needed. Such investigations also offer opportunities to make recommendations regarding mitigation measures, disaster preparedness, and emergency responses for better preparing communities for future disasters."
TMS, working together with the Council for Masonry Research (CMR) sponsored the investigation. The Society's Coordinator for their Investigating Disasters Program, Arturo Schultz (University of Minnesota), and TMS President Max Porter (University of Iowa) requested that authorities in the Gulf States region grant the team access to disaster areas and share information with the team members.
"These scientific investigations are part of a comprehensive disaster hazard-reduction effort underway in this country and cooperation from local officials enhances the team's effectiveness in carrying out their critical task," Schultz says, adding that a report of findings is expected to be available from TMS in the near future. Hurricanes are not isolated events that affect only the Atlantic and Gulf Coast states.
Sylvester Schmidt, Chairman of the Board of the National Concrete Masonry Association said, "As we are seeing from Katrina, the social and economic impact of a hurricane can cascade throughout the country immediately following the event. The President of the United States noted in his September 15 address to the nation that 'communities will need to move decisively to change zoning laws and building codes to avoid a repeat of this disaster.
' There is also a need to revise our thinking about the building materials specified for reconstruction. Particular attention needs to be paid to both proper construction methods and the use of substantial materials. Concrete masonry is clearly an appropriate choice to help to minimize future losses."