base isolation systems for seismic designs

eric johnston (98768299@MAIL.WSU.EDU)
Sun, 19 Apr 1998 13:39:35 -0700

Message-ID:  <199804192039.NAA26021@cheetah.it.wsu.edu>
Date:         Sun, 19 Apr 1998 13:39:35 -0700
From: eric johnston <98768299@MAIL.WSU.EDU>
Subject:      base isolation systems for seismic designs
To: CIVIL-L@hermes.csd.unb.ca

Last Friday I was in a seminar given by the structural engineer who designed
the seismic retrofit of the historic San Fransisco city hall.
Part of the design was the installation of about 500 rubber base isolators.

I thought that was that was pretty neat

Anyways I got thinking and have a couple questions

1)  Are there problems with differential settlements with base isolators?

2)  Are there  problems with diffential movement of isolators?

3) What are the best ones to use, rubber, lead core rubber, or friciton
pendelums?  Are there others?  Here at  WSU we are doing some research on
shock absorbers attached to bracing members.

Questions, comments, or threats are welcome

P.S. thanks for the great comments on the LRFD-USD topic

Eric and Linda Johnston
98768299@mail.wsu.edu