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COORDINATION WITH CODES AND STANDARDS <br />Wind provisions of ASC.E 7-10 are recognized in the 2012 IRC, the 2012 IBC, and the 2012 <br />WFCM, however, each of these documents addresses implementation of ASCE 7-10 wind <br />provisions differently. <br />IBC adopts ASCE 7-1 0 provisions for wind design by reference and incorporates ASCE 7-1 0 <br />wind speed maps. A conversion of mapped wind speed to an ASD basis (i.e. V�'Sd per, 2012 IBC is <br />calculated as Vasa = V,,,, x 0.6") is added to the IBC to coordinate with previously established <br />IBC wind speed triggers, many of which remain unchanged. For wood construction, the <br />conversion from ultimate to ASD-based wind speed is needed to use: tables for attachment of <br />wood structural panels for wind, wind applicability limits for conventional light -frame <br />construction, and wind uplift connector requirements in 1BC Section 2308. <br />Within the IRC, new maps illustrate ASD-based wines speeds. The IRC format of the wind speed <br />map eliminates the need for conversion of the mapped value as is done in the IBC; however, the <br />mapped contour lines do not directly align with those in ASCE 7-10 maps incorporated in the <br />IBC.. <br />The 2012 WFCA11 will include ASCE 7-10 Risk Category It wind speed snaps and tabulate <br />requirements for wind speeds ranging from 110 mph to 195 mph for both Exposures B and. C. <br />The reinstatement of Exposure D in ASCE 7-10, is a new consideration for the WFCM as prior <br />editions provided tabulated requirements for Exposure B and C only, with a conversion table to <br />adjust tabular values in Chapter 2 for Exposure D. The removal of the occupancy factor <br />adjustment to wind loads will generally limit applicability of WFCM load tables. While prior <br />W F,CM load tables were based on occupancy category 11, they were easily adjusted by the <br />occupancy factor to estimate loads for other occupancy types. <br />CONCLUSIONS <br />Changes in wind design provisions introduced in ASCE 7-10 produce the greatest differences in <br />design velocity pressures for areas within the hurricane prone region. For Exposure D sites, <br />design velocity pressures can be both larger (Boston, 1'v11A) and smaller (Virginia Beach, VA) <br />than those determined in accordance with ASCE 7-05. For Exposure C sites, design velocity <br />pressures were as much as 28 percent smaller than those calculated using ASCE 7-05 for sites <br />evaluated in this paper. Changes to design velocity pressures followed the same trends for Risk <br />Category 11,1I1, and IV buildings. <br />Revised minimum wind loads in ASCE 7-10 will reduce occurrences where they control in licit <br />of more detailed methods for calculation of wind pressures for MWFRS. Additionally, changes <br />to wind speed maps and load factors for wind are coordinated with revision of familiar wind <br />speed and wind load triggers. For example, hurricane prone regions in ASCE 7-1 0 are associated <br />with mapped wind speeds of 115 mph and higher instead of 90 mph and higher in ASCE 7-05; <br />with similar wind speed revisions occurring for definition of wind-borne debris regions. <br />Similarly, the minimum wind load for walls is given as 16 psf in ASCU 7-10 instead of the <br />familiar 10 psf in ASCE 7-05. <br />ASCE 7-10 WindProvi;sions 9 Line/Crulbraw-ne <br />