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Column tree moment frame

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Dear fellow engineers,
 
I am working on the seismic upgrade o the soft story wood building.  It is fairly large 130x130 three story, 100 year wood framed building.  There are two elevations of open fronts on the West and North sides of the buildings that we are bracing with 2 bays of moment frames.  The owner did not want to use braced frames and even with grade beam fixing the bottom of the columns we are ending up with pretty hefty W27 sections for beams and columns.  Affecting more stores by adding more bays is not feasible.  In the past when we had to use anything bigger than W14 (I think that biggest we used was a W18 column) we specified Ordinary moment frame per FEMA or intermediate moment frames per CBC with all the special detailing around backup bars and access holes. 
 
Here are my questions:
 
1. Would that still applicable when using much bigger sections such as W27?
 
2. I am not up on all the recent research on steel moment frames, but can we still use the rigid Column Tree design as described for example in Structural Steel Educational Council Steel Tips http://www.steeltips.org/steeltips/index.php - as of 04.1997?
 
Thank you very much,
 
Alexander (Sasha) Itsekson, SE
Enginious Structures, Inc.
Oakland, CA
510.601.1646
www.Enginious-Structures.com