design wind load for Valparaiso, Chile 1

[EngineerofSteel]

I need to find the wind load for Valparaiso, Chile. I have a 9 year report (wunderground.com), but what I really want is a wind map showing design zones.

I have had no luck.

I do not have IBC book... I am especially interested in an online source.

All suggestions appreciated.

Thanks, DD

 

[dig1]

Hi DD,

I believe that the latest edition of NCh 432 of 71 is the second edition from 1994. You can contact the Instituto Nacional De Normalization, last number I have is phone 011-56-2-672 46 38 (they sell the standards)but on the web at

http://www.inn.cl

What the edition of the code referenced above states in 6.3(paraphrased) is that the instantaneous wind speed of the site should be used based on 20 years worth of measurements and with the approval of the Inspecting Authority. 6.4 states (again paraphrased) is that if the statistical wind speed is not available, then the Table (Table 1 with the basic pressure (which obviously changes with height) are to be used.

I recently did a two projects in Chile and the owner specified ASCE 7-02 along with a wind speed.

However, with you being near Valpo, I would expect that seismic will govern your design. You will definitely need NCh 2369 for any industrial structures including tanks, pressure vessels, equipment, etc. One of the projects I worked on had lateral coefficients of approximately 50% plus a vertical coeficient of nearly 40%. Seismic easily controlled over wind.

You will likely need to do shear keys and there details required for the projection of anchor bolts above the top of rough pour and in the anchor chairs (spacing between top and bottom plates of anchor chairs), amount of thread below top of top plate, etc. A dynamic analysis may be required (guidelines in NCh 2369).

None of this is difficult but you need to be aware before you start.

You should also check your customers specifications because they often

The seismic designs then need to be reviewed by a person with appropriate experience in Chilean seismic design. The exact definitions are of an appropriate review are given in NCh 2369. There are two firms I know of that do this work; cost wise it is reasonable and the turn around is fairly quick. I strongly suggest that this review be performed prior to the start of fabrication.

I hope this help.

Patrick