ISA Presents New Research on Wind Loads for Signs
ISA introduced new research on wind load criteria for outdoor signs to the American Society of Civil Engineers during an April 12 meeting at ASCE headquarters in Reston, VA. This research aims to improve the current level of knowledge on sign engineering and representatives of ISA, OAAA and Texas Tech provided useful background for the ASCE 7 committee on the recently completed research project at Texas Tech University. Funded jointly by ISA and OAAA, this research provides independent evaluation of the current wind load criteria for outdoor sign structures. These requirements originally were adopted into the ASCE 7-05 standards and, subsequently, were incorporated into the current ASCE 7-10 standards and corresponding building codes. The Texas Tech research project is headed by Douglas A. Smith, Ph.D., P.E., Associate Professor/Associate Chair of Civil Engineering and Delong Zuo, PH.D., Associate Professor of Civil and Environmental Engineering. During the April 12 meeting, Dr. Smith, a voting member of the ASCE 7 Committee, also presented information on these research findings from the university’s perspective.
In evaluating the revised ASCE standards in 2006 and 2007, the ISA Mechanical & Structural Subcommittee originally expressed concerns that new design requirements might be inappropriate for commercial-type sign structures. ISA and OAAA initially communicated these concerns to the ASCE 7 Committee in 2007 prior to launching the Texas Tech study. Phase 1 of this research involved field analysis of a full-scale sign structure at the Texas Tech Wind Engineering Researc.h Field Laboratory in Lubbock and findings were published in November 2009. Based on results of this study and related wind tunnel testing, a decision was made to proceed with further research comprising a full battery of wind tunnel tests analyzing a broad range of typical sign-model configurations.
This research was completed in December 2011 and the final TTU report will be published by June 2012. After publication, ISA and OAAA will begin to prepare a corresponding proposal to change wind load requirements for sign structures in the ASCE 7-16 standard. This proposal will be submitted during the second half of 2012. Questions or comments should be addressed to Bill Dundas, ISA Director of Technical & Regulatory Affairs: [email protected].
