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Re: Wood - Lateral columns and knee braces (kickers)

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Dennis,

I have used the knee braces before and it seems to have worked well.  For the 
type of loads you have it should work out fine.  I would use a minimum of a 4x4 
brace to get the edge distance.  I have used lag bolts for end columns and 
through bolts for inner columns, where I had braces on both sides.  

I think the knee braces look better than a base tube.  Some warn against trying 
to develop a moment connection with wood.  In this case the tube base is a loose
fit with only the bolts to keep it tight. 

Ed Haninger, SE
Fluor Daniel

______________________________ Reply Separator _________________________________
Subject: Wood - Lateral columns and knee braces (kickers)
Author:  "Dennis S. Wish PE" <wish(--nospam--at)cwia.com> at fdinet
Date:    9/2/98 5:02 PM


I should know the answer to this one by now, but I think it has to do with 
degree.
I am designing a Patio Trellis which is supported by four 6x6 DF #1 columns 
at the unsupported edge. The shear on the supported edge is distributed into 
a long shear wall and therefore no problem.
The columns are 10'-6" from the face of the wall.
I have designed the lateral being extremely conservative. I distributed 30% 
of the weight of the structure (12 psf) into four columns. This amounted to 
177 lbs per columns at 8' above the slab.
The moment at the base of the columns would be approximately, 1420 ft-lbs.
     
I don't want to embed wood into concrete and decided to create a pad footing 
with a pedestal set six inches above the top of finished slab. I intended to 
place a TS6x6x1/4" sleeve into the foundation and slip the wood column into 
place. This way the wood can develope moment without failing relative to the 
direction of grain.
     
This is a rather costly solution for a remodel. I wanted to get an opinion 
about the use of bolted knee braces where the lateral load is relativly 
small. The approach is to use a 2X6 on each face of the column bolted 
through and connected to the beam which is a 6x8 DF #1. The connection of 
the column to beam is done with conventional Simpson CC66's (ECC66 at each 
end column).
     
I have not modeled this, but wanted to get a second opinion before investing 
the time.
     
BTW, the top of the trellis is simply 4x10's @ 32" o/c with 2x2's at 12" o/c 
above that.
     
I need to finish this tomorrow, so if anyone has an opinion, please let me 
know as soon as you can.
     
Thanks for the help
Dennis Wish PE
     
     
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<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial size=2>I 
should know the answer to this one by now, but I think it has to do with 
degree.</FONT></SPAN></DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial size=2>I am 
designing a Patio Trellis which is supported by four 6x6 DF #1 columns at the 
unsupported edge. The shear on the supported edge is distributed into a long 
shear wall and therefore no problem.</FONT></SPAN></DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial size=2>The 
columns are 10'-6&quot; from the face of the wall.</FONT></SPAN></DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial size=2>I have

designed the lateral being extremely conservative. I distributed 30% of the 
weight of the structure (12 psf) into four columns. This amounted to 177 lbs per

columns at 8' above the slab.</FONT></SPAN></DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial size=2>The 
moment at the base of the columns would be approximately, 1420 
ft-lbs.</FONT></SPAN></DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial 
size=2></FONT></SPAN>&nbsp;</DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial size=2>I 
don't want to embed wood into concrete and decided to create a pad footing with 
a pedestal set six inches above the top of finished slab. I intended to place a 
TS6x6x1/4&quot; sleeve into the foundation and slip the wood column into place. 
This way the wood can develope moment without failing relative to the direction 
of grain.</FONT></SPAN></DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial 
size=2></FONT></SPAN>&nbsp;</DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial size=2>This 
is a rather costly solution for a remodel. I wanted to get an opinion about the 
use of bolted knee braces where the lateral load is relativly small. The 
approach is to use a 2X6 on each face of the column bolted through and connected

to the beam which is a 6x8 DF #1. The connection of the column to beam is done 
with conventional Simpson CC66's (ECC66 at each end column).</FONT></SPAN></DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial 
size=2></FONT></SPAN>&nbsp;</DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial size=2>I have

not modeled this, but wanted to get a second opinion before investing the 
time.</FONT></SPAN></DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial 
size=2></FONT></SPAN>&nbsp;</DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial size=2>BTW, 
the top of the trellis is simply 4x10's @ 32&quot; o/c with 2x2's at 12&quot; 
o/c above that.</FONT></SPAN></DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial 
size=2></FONT></SPAN>&nbsp;</DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial size=2>I need

to finish this tomorrow, so if anyone has an opinion, please let me know as soon

as you can.</FONT></SPAN></DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial 
size=2></FONT></SPAN>&nbsp;</DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial size=2>Thanks

for the help</FONT></SPAN></DIV>
<DIV><SPAN class=590564723-02091998><FONT color=#000000 face=Arial size=2>Dennis

Wish PE</FONT></SPAN></DIV>
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