Wind Load Cases & Seismic ( vertical coeffiecient Vector)

Posted by: Azley

Wind Load Cases & Seismic ( vertical coeffiecient Vector) - 02/22/13 01:00 AM

Dear Sirs, Friends

I have doubt for Wind Load Cases & Seismic Analysis for vertical components.

1) Wind Load Cases.

I read the ASCE 7 & TR of COADE, based on these I built the Load Cases as +x,-X,+z & - Z wind loads. Sepearte & Individual Load Cases.

The Loads what we are considering are one (single) direction,but why we are not adding all directions occasional loads. WIN1+WIN2+WIN3+WIN4.

Combining PURE WIND LOADS with SUS case.?This is what i asking is addition of load case with Individual wind loads.

W+P1+WIN1+WIN2+WIN3+WIN4 =======????? (ADDITION TO INDIVIDUAL WIND LOAD)


Is this not require?

2) Seismic Analysis

As piping is generally resting by Vertical Restraints, hence, by gravity law, the pipe weight almost sustain by these Vertical suppports than if we again check the vertical seismic coeffeiceint (Vector) will it not over conservative?

My understanding is only Horizontal vectors are suffeciient for Seismic Analysis.

I am awaiting your guidance.
Thanks.
Posted by: BelladB009

Re: Wind Load Cases & Seismic ( vertical coeffiecient Vector) - 02/22/13 05:53 AM

Dear friend,
1. In short wind when it is blowing , blows in only one direction and so we consider it in only one direction.

2. Yes i agree to ur point on seismic from loads point of view applying vertical vector .



Regards,
Bharat Bellad
Posted by: mariog

Re: Wind Load Cases & Seismic ( vertical coeffiecient Vector) - 02/26/13 04:28 AM

You may consider the vertical acceleration as modifying the weight of components/ elements as +/- [Av*100] %, where Av is the fraction of g representing the vertical acceleration.
You would be interested to evaluate the consequences on stress piping and on supports.

Best regards.