# Redundancy Factor

• To: seaint(--nospam--at)seaint.org
• Subject: Redundancy Factor
• From: rlewis(--nospam--at)techteam.org (Richard Lewis)
• Date: 09 Jun 1999 01:45:38 GMT
```I would like to start a new thread on the Redundancy Factor, Rho, of the 1997
UBC.

I have a 2 story concrete framed building.  Total base shear is 46.2 kips.
Worst case shear in a frame line is 12.2 kips, with 4 columns.  Ground floor
area is 2312 SF.  Now for a multi bay frame I use 70% of 2 columns to
calculate Rho.  I get

ri=0.7*(12.2*(2/4)/46.3 = 0.092  (from paragraph in 1630.1)

Rho = 2-20/(0.092*sqrt(2312)) = -2.5 (eq. 30-3)

Now this Rho is less than 1.0 so Rho min = 1.0  (paragraph in 1630.1)

My question is, did I do this right?  Can I calculate a Rho value less than
zero?
__________________________________________________

Richard Lewis, P.E.
Missionary TECH Team
rlewis(--nospam--at)techteam.org

The service mission like-minded Christian organizations
may turn to for technical assistance and know-how.

```