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I am planning to build a corner pergola over my deck. Pergola is 8ft long from the corner on either side forming a triangle on the top. I have used four 4x4 posts (8 ft) attached to the deck headers using three 1/2" carriage bolt per post. How do I reduce wobbling when shear force is applied to simulate wind condition?

Since I am new to the forum, I am unable to post a picture. Imagine it's triangle with two beams parallel to the side of the deck forming a 90 degree angle and the third beam joins these two beams to form a triangle. Third beam has no supporting post. On top of the triangular beam, I have notched joists.

DMoore
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user14655
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1 Answers1

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You need to install knee braces every where you can. (The diagonal piece)

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Ideally, the ends should be tightly dadoed a small amount into the beam and post to minimize the inevitable play that develops in connections made solely of mechanical fasteners. The bigger the brace the better, within reason. The best bracing would be the grand-daddy of knee braces-- X-bracing.

bcworkz
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