This is an issue that is frequently overlooked. You are right, the stiffness of the ramp is a problem in seismic design of ramped structures such as parking structures. The best treatment I have seen on this topic is a paper written by the team at Watry Design, Inc. and printed in the PTI journal. It is titled "Seismic Analysis and Design of Ramped Parking Structures" by John Purinton and several others, 2003. Watry incorporates special detailing in their structures to ensure that the load is more likely to go where it is intended to go.
Buckling Restrained Braces, anyone?
From: Rhkratzse@aol.com [mailto:Rhkratzse@aol.com]
Sent: Thursday, July 12, 2007 9:43 AM
To: anant_27@yahoo.com; seaint@seaint.org
Subject: Re: Story shear for ramps; ramps as braces?
Just curious; I don't design parking garages any more.
Ralph
In a message dated 7/12/07 8:30:18 AM, anant_27@yahoo.com writes:
I am designing a parking garage with ramps in both directions (dog-legged). How do I determine my diaphragm extents? Is it okay to take half the weight of the ramp to the story above and below to calculate story shears?
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