Wind

Jim Riemenschneider has chaired the wind committee since 2007.  Prior to coming to Oregon, he had worked as an engineer in Michigan where he was familiar with the ASCE 7 wind load procedures.  As the UBC procedures were being brought to an end, this familiarity fostered his understanding of the wind design requirements in the IBC and ASCE 7, which are now the standard. 

An opportunity to create an alternate to the lengthy methods in ASCE 7 led to section 1609.6 “Alternate all-heights method” in the 2009 IBC.  Future endeavors will continue to center around our use of ASCE 7 design methodologies and changing toward strength-design standards, especially how they impact our future 2012 IBC and 2013 OSSC.

Watch this eye-opening video of full scale building testing performed by the  Insurance Institute for Business and Home Safety (IBHS), which brings new light to a few age-old and related questions, such as  “Does seismic or does wind control one’s lateral design and analysis?”  and “Does my building need seismic detailing even if wind loads control over seismic loads?” (Remember, OSSC Section 1604.10 truly answers that question.)  And with that, we often overlook “enclosed” versus “partially enclosed” wind design, because there can’t be that much difference, can there?

In this video, inside IBHS’s 145’ x 145’ x 70’ tall testing chamber, two 30’ x 20’ one story masonry buildings, each with fully detailed roof assemblies but different wall assemblies, are put to the test.  One received a higher standard of wall construction that is minimally more expensive than did its unreinforced ‘neighbor’.

Have you ever known a roof to actually tear a masonry wall upward in tension?  Watch this video as windows break and one building gets ripped apart from internal and external wind pressures (from 136 mph peak gusts) and its neighbor ‘stands tall’:

The ATC website can provide a web page where you can input a project’s location (via latitude and longitude).  the page will then return the ASCE 7-10, -05, or 02 design wind speeds and a map of the location you input.  It also has a tab that links you to mapping sites in an effort to help in locating a project’s latitude and longitude.

The link is at follows:  http://atcouncil.org/windspeed/

Big caveat: What it does NOT do is obtain design speeds within “Special Wind Regions”, so it will blank with no results, say for example, here in the Columbia Gorge or out at our coast.