Metal Siding/Roofing Shear Panels

[cuels]

I am analyzing an existing structure that was built without a building permit. I am to analyze the structure and provide recommendations to correct any problems I encounter. The building is framed using 1-1/2" square tubing to create 4'x8' openings (for rigid polystyrene insulation) as best as possible. The building is 26'L x 14'-4"W with 8' cieling. The roof is a "lean-to style" roof with a 4 degree pitch.

The only shear I can assume is either the welded connections of the 1-1/2" tubing...but it seems a little extensive to calculate that for such a simple building, or the metal ribbed siding. I can't find any information on the shear strength provided by metal ribbed siding. Does anyone have a good resource for quick information, or a method for calculating the shear resistance of this panel system?

Thanks,
cuels

 

[msquared48]

Looks loke a pretty solidly built structure from the photo.

I woulod not rely on any metal siding less than 22 gage in thickness. If it is composed of the 28 or 29 gage stuff normally used, forget it and to to interior welded metal straps at this stage of the game.

Hopefully you can weld in the proximity - otherwise use metal screws.

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask

 

[hokie66]

Siding is to enclose space and provide watertightness. It is not a structural material.

 

[DaveAtkins]

The siding does appear to be structural (the type used on agricultural buildings--Fabral is one manufacturer). Look at the Post Frame Handbook (I am forgetting the exact name) or at the Fabral website to get diaphragm values. The siding can be used as a roof diaphragm and as a shear wall.

DaveAtkins

 

[MiketheEngineer]

I tend to agree w/ Dave. Look at the National Post Frame Builders. Some goo info there.

 

[rscassar]

I do not consider metal roof or wall profiles as having diaphragm capacity.

Please read these threads as they have discussion on this matter.

thread507-277251
thread507-270224

There are manufacturers of insulation panels (referred to as sandwich panels; light gage metal sheeting which is glued to a core) who have tested their products to confirm that they are capable of working as a diaphragm. If you have one of these products, the best thing to do would be to contact them and see if they have any published test data to confirm that there product can be used to act as a diaphragm. It is best to ensure that any testing has been done at an accredited laboratory as stipulated in any building code that you must comply with.

One manufacturer of sandwich panels that have done such testing and I have worked with in the past is Ritek.

http://www.ritek.com.au

Once you have confirmed that the 'rigid polystyrene insulation' can be used as a diaphragm you will then need to go through the design to ensure that you have adequate transfer of lateral forces through the diaphragm and into the boundary elements.

 

[DaveAtkins]

National Frame Builders Association has done extensive testing on the type of roof and wall panels which we are discussing, and they have good diaphragm and shear wall capacity.

They tested Wick Agri Panel, Midwest Manufacturing, Grandrib 3, Walters STR-28, Metal Sales Pro Panel II, McElroy Metal Max Rib and Alumax Power Panel.

DaveAtkins

 

[ToadJones]

Should be an easy building to stiffen up with some light angle bracing if you encounter problems.