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Wood - Radiused GLB Roof beams - outward thrust deflection question

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We are remodeling a custom home in the desert. The architect has chosen to
design the roof with a 31' radius GLB spaced at 11 feet apart. The radius
beams will bear upon a post and beam structure above the existing interior
walls. The beams perpendicular and at each end of the radius beams will be
supported by steel columns and flag pole type foundations to distribute
gravity and lateral loads from the new roof diaphragm.
The roof will be lightweight constructed of 2x10 purlins between the radius
beam (girders). The roof will be sheathed in 5/8" Ply and covered with a
metal roof material.
The roof will also contain R38 batt and a 1/2" gypsum ceiling which will
actually be gusseted down by plywood to create a Moorish curved and arched
interior ceiling finish.

My concern is that the radius beams will have a horizontal deflection due
the the dead load which I believe must be anticipated and compensated prior
to placing the columns supporting the beams. However, most of the deflection
may not be appearant immediatly even though the GLB's are not as prone to
creep as sawn lumber.
I have recommended placing the columns supporting the beams adjacent to the
existing load bearing wall for the adjacent roof and creating a second wall
to hide the columns and allow for their movement due to both deflection
(horizontal) and from lateral drift.

Has anyone had an experience in this area that can guide me with suggestions
and possibly some suggestions for finding design criteria for radiused
GLB's. I have the AITC Timber Construction Manual although it is an old
third edition.

Thanks in advance for your help.

Dennis Wish PE