Inspection of Sign Structures 1

[tft2001]

I am in the process of beginning to perform a field evaluation of a 40 year old, 3 pipe column, sign structure that is approximately 50 feet in height. I have a preliminary procedure in performing this work, however, I was wondering if anyone has any links to references associated with field evaluations of these types of structures?

 

[Ron]

I doubt there's anything specific to commercial signs, but there are two sources I would check...

1. You state department of transportation (they have to inspect their signs and probably have a protocol for doing so). Check other states if yours doesn't have one.

2. A sign has similar structure and exposure to electrical transmission structures and towers. Check sources for both of these and you should hit something.

 

[rscassar]

I don't have any experience with field evaluation for these type of structures but there was a recent thread regarding the assessment of existing steel structures.
thread507-278628

There were some good checklist items brought up in this thread including:

paint conditions
member thickness-section loss
fatigue cracks
bolt conditions
weld conditions-weld cracking
local corrosion
buckling

 

[Catacus]

tft2001, if those are the typical billboard structures of pipe you see along highways, AEC in Minneapolis did an extensive structural and condition review for one of the big sign companies (most were in Florida), back in the 90's. They had field inspectors measure all relavent dimesions and thicknesses, sent the info home and the put in a custom program that did all or most of the checks and spit out what needed to be reinforced. They checked hundreds, many slightly different, so it justified the program etc.

 

[ATSE]

tft,
One common feature to light poles, communications poles and signage is an access port near the base. This is usually for pulling electrical wires that stub up thru the foundation.
Do not ignore this opening, or assume that the reinforcing around the opening is sufficient. This location is a potential problem zone for fatigue cracking near the base of the port.

 

[csd72]

Blodgett Design of tubular structures is a good reference if you need to any in depth design of openings, connections e.t.c.

A few questions that I would look for:

- was the structure designed properly in the first place
- was the structure built properly
- has the structure degraded.
- is the degradation in a critical position
- is there possibly any hidden degradation
- do modern codes require more stringent criteria(i.e seismic resistance) that the client should be made aware of?
- any other side issues i.e. loose panels, safe access e.t.c.