Load Distribution Question
Load Distribution Question
(OP)
I am designing a bridge on private property that the owner would like to be wood. However, due to the span and clearance limitations, I will be using timber planks over steel stringers. I was comparing load distribution between AASHTO 9.9.3.1 and table 4.6.2.2.2a-1. The 36" spacing or 6x nominal plank thickness limitation bothers me. In the commentary, the code states that the approximate methods of analysis are not valid and two dimensional methods of analysis are recommended.
Now, I'm having difficulties with the "Orthogonal plate theory" method, especially considering a wood plank deck. Can someone shed some light on this?
Now, I'm having difficulties with the "Orthogonal plate theory" method, especially considering a wood plank deck. Can someone shed some light on this?





RE: Load Distribution Question
RE: Load Distribution Question
RE: Load Distribution Question
RE: Load Distribution Question
One thing I should have pointed out earlier: Table 4-etc deals with the DF for the stringer design. Chapter 9 deals with the actual deck design.
What live load are you using? HL-93? If this is access to a private home you could justify using something less, for example the larges anticipated fire truck.
RE: Load Distribution Question
Thanks!
RE: Load Distribution Question
RE: Load Distribution Question
This will be slightly conservative and there is nothing wrong with that.