Light pole stiffener plates

[Tstruct]

Hello,
Please have a look at the attached image. The image is a detail of a base plate connection of a street light pole in which I have marked the stiffener plate. I have to design a similar connection but I am unable to understand what is the purpose of these stiffener plates here and how to determine what force is it subjected to and how to determine it's dimensions? In reality I have seen light poles without any stiffeners, with stiffeners in one direction only and stiffeners in both directions. Are they really required? Can we avoid it at all?

Thanks.

 

[canwesteng]

You can avoid it with a thicker base plate.

 

[BridgeSmith]

You can avoid it with a thicker base plate.

Correct, and you should. Connections with stiffeners have proven to be fatigue-prone details.

Get a copy of the latest LRFD Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals. Look carefully at Section 11.

 

[Ron247]

I would use thicker plates, cheaper and probably more reliable. The stiffeners in the detail look somewhat useless to me. Stiffeners try to route bolt loads towards the stiffener and thus reduce plate thickness. The locations of those stiffeners look like the corners of the plate will still dog-ear assuming the drawing is to scale.