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FEMA 273

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I would like to thank you all for the advices I was given in order to get FEMA 273 document.   Right now I am downloading it.
 
I am in Mexico City and we are very concerned about what is changing in seismic design codes around the world.   Mainly cause, as you probably know, Mexico City is localized on a deep-layered soft soil and the amplification of the ground motion related to site effects has a great deal on seismic response, resulting in a high earthquake prone area.
 
Our codes are not as fast-evolving as american´s are, besides the fact that building´s general structural arrangement are different.  We almost always use moment resisting frames both in concrete and steel structures, instead of one gravitational system and other lateral force resisting one.   Specifically with SAC Interim Guidelines´s origin, the fact of not depending on a few moment resistant connections results in thinner steel connection plates than if we don´t.   Some of us believe that having thinner connection elements have provided more overall ductil behaviour in Mexico´s steel buildings.  
 
It doesn´t mean that our buildings performed the better way they should, as was in part evidenced by the great damage and loss of life during the 1985 mexican earthquakes, but our seismic design requirements are some different than yours.
 
I want to highlight this, because sharing information among colleagues help us in develope improved structural designs, incorporating concepts learned from other countries.
 
According to this, I have been reading your comments about both FEMA 273 ,274 and UBC-97 application on the office desk.   It has been very interesting and I would like to interchange opinions with you after I read it.
 
Fabricio Rosales, P.E.