Where will I put a Shear Wall?

[patrick526]

Hello! I am a newbie and I hope you guys will have some patience answering my questions. I tried hard looking for books that can tell me when and where am I gonna put a shear wall along the whole length of wall, but none of them really gives the rule when to provide a shearwall and where will I put a shearwall exactly on a specific location?

Let's say I have a 60 ft. span, 8' high masonry wall. Where will I put a shear wall? I remember an older engineer told me before that the rule of thumb for this provide a shear wall every "20 ft." of wall span, but there is no concrete basis for this. I would wonder if you could shed me light regarding this.

Thanks!

 

[johnp]

Hi patrick526,
The logic of your question is a little unclear. Walls come in different types - free-standing, parts of buildings, retaining structures, fencing, and so on.

I suspect you are talking about lateral restraint - i.e. what gives a free standing wall sufficient strength to resist wind or earthquake. Lateral restraint can be provided by piers, built in columns, steelwork, and so on. There are so many variables that usually authors do not like to go into so much detail, or they'd have to write a whole book about it. I would suggest 2 sources

1 - Talk to your brick association technical support department,

2 - Check out the building bye-laws. In the old days they used to go into slenderness ratios, panel sizes, and so on.

The other thing to watch is movement of the brickwork. What stops the brittle brick panels from cracking?

3 - some bricks swell, or expand. How do you cater for that?

4 - foundations are subject to differential settlement. This can cause cracks to appear. What are your founding conditions?

5 - are you using common stock brick, or engineering brick? The harder the brick, and the stronger the mortar, the more prone to cracking due to brittle movement. The weaker lime/sand mortars used to allow the joints to yield a little, thus preventing cracking.

Regards - Sgt John.Rz
University Regiment (retired)

http://www.latviantourists.com.au

Johnp.Rz

http://www.mets.net.au

 

[patrick526]

Thanks for the response Sir. I'll look into that.