ASCE 7-10 Wind Loads Ronald Cook1, Larry Griffis2, Peter Vickery3, Eric Stafford4 1 Civil and Coastal Engineering, University of Florida, Structures Division, Walter P. Moore and Associates, 3 Applied Research Associates, 4 T. Eric Stafford & Associates, 2 ABSTRACT ASCE 7-10 “Minimum Design Loads for Buildings and Other Structures” contains several changes regarding wind loads. The major editorial change is a complete reorganization to a multiple-chapter format as done previously for seismic loads with the objective being to make the provisions easier to follow.

Minimum Design Loads for Buildings and Other Structures, ASCE/SEI 7-10, provides requirements for general structural design and includes means for determining dead, live, soil, flood, snow, rain, atmospheric ice, earthquake, and wind loads, as well as their combinations, which are suitable for inclusion in building codes and other documents.

Technical changes include the introduction of new wind speed maps to be used with a 1.0 load factor for LRFD and a 0.6 load factor for ASD, the reintroduction of Exposure D for water surfaces in hurricane-prone regions, and revised wind-borne debris regions. A new simplified procedure for buildings up to 160 ft has been added based on the provisions for buildings of all heights. INTRODUCTION The major changes to the wind load provisions of ASCE 7 introduced in ASCE 7-10 are: • • • • • Reorganization of wind load provisions Wind speed maps Re-introduction of Exposure D in hurricane-prone regions Wind-borne debris region Simplified procedure for buildings ≤ 160 ft This paper presents a general background on the basis for these changes. Thirty other changes related to wind loads were included in ASCE 7-10.

The majority of these changes were editorial but some did include technical changes. These include: • • • • Minimum wind loads Improved exposure and roughness examples Revisions to low-rise “envelope” method Rooftop equipment REORGANIZATION OF WIND LOAD PROVISIONS The wind load provisions of Chapter 6 in ASCE 7 have been reorganized into 6 new Chapters. In recent years, there has been much discussion about the layout and presentation of the wind load provisions in ASCE 7. While, ASCE 7-98 did make some improvements to the format (introduction of the 3 Methods), much of the important information was buried deep within the paragraph numbering. In addition, Method 2 Analytical Procedure actually contained several analytical methods embedded within the section (e.g., Buildings of All Heights and Low-rise Buildings). While the provisions were technically correct and properly numbered, understanding and applying the appropriate wind loads could be somewhat cumbersome.