Mike,
The limitation is under section 2308.2 #5 "Roof trusses and rafters shall not span more than 40 feet between points of vertical support."
AELLC,
I went back through prior editions of the building code and this limitation was added in the 2000 IBC. Your thought about the plate strength...
Hello All.
I had a question from an architect recently that made me think. The limitations for specifying wall bracing under the conventional light frame guidelines in the 2009 IBC state that the truss spans shall be less than 40' (section 2308.2).
A year or so ago, I went to an ASCE...
Thanks for the thoughts,
I have looked at the kern point as a goal under operational loads. And typically, if you can meet the allowable bearing stress and a safety factor of 1.5 for slidng and overturning, the e is within kern.
For extreme events like a seismic event, I have approached this...
Hello,
With respect to the design of concrete, cantilevered retaining walls, I have been wondering what the consensus of the group is.
In designing the walls, keeping the eccentricity within the middle 1/3 of the footing generally means that you have no uplift on the heel of the footing. In...
Hello,
I have a question that is bugging me. I am working on a residential project where the foundation is supported on 3" dia pin piles. I specified galvanized pipe pipe, but of course it is expensive.
I have been thinking that as these piles are driven into the ground, there is a good...
Just a quick followup.
I have a little background in bridge design. Consequently, I have looked at concrete rails such as the one you are describing as being similar to bridge rails. The LRFD design manual Table A13.2-1 gives a force and a width to apply the force based on test level. The...
For what it is worth, I recently put together a bid for an unreinforced masonry building rehab. I also found that the IEBC was not a referenced document in the IBC. I went through the juridiction that I would be working in nd found that they had not adopted the IEBC. Before completing my...
Splitrings,
I do the exact thing that you do. I usually will check the NDS tables to verify my spreadsheet. You never know if a formula I programmed will cause an error.
dhengr,
You know, I really like knowing the mode of failure for numerous reasons, not the least of which is the ductile...
The NDS tables are nice for most quick calcs, but nothing beats programming a spreadsheet to do these connection calcs. The strength of your bolt factors into the K3 calculation, and does have an effect on the strength of the connection. A check of my spreadsheet shows that a 90ksi Fy bolt...