Cell Tower Structural Analysis for Co-Location 2

[dmx]

I am looking for some background information related to which standard should be used when performing a structural analysis of an existing cell tower where additional equipment is to be added to it. I have found the TIA/EIA-222-F standard and a new revision TIA/EIA-222-G that was published in 2006. Revision G increases wind and ice loading. Which should be used and who determines which guidelines to use. Is it state, federal, local or industry regulated.

Thanks

 

[oldrunner]

The 2006 IBC indicates F. I would check with your state authorities. Refer to section 1609.1.1. Section 3108 refers to Radio and Television towers.

 

[zestructural]

dmx,

Check with your client for which version of code F or G he wants you to use. For example, Crown Castle International requires their towers are analyzed accordance with G-code. Also, check with the local code enforcement department where the tower is located. The industry uses G-code now.

 

[VoyageofDiscovery]

Seeing that you are asking about which code to use, I assume you have not done this type of analysis before.

If this is a guyed tower, analysis for this type of structure is fairly complex. Make sure you have the proper engine (ie GuyMast or ERI software) to do the analysis.

VOD

 

[dmx]

Actually....I am on the review end and was wondering from a municiple standpoint (planning board approval) which one we should be asking for the structural to be done under.

 

[VoyageofDiscovery]

The engineering is to be completed under TIA/EIA G which is the most current. I have seen counties in Florida requiring higher wind loadings, this was the only exception though at the time. The designs must be stamped by an engineer licensed to practice in the state.

 

[adurbin]

Our company analyzes all towers (built prior to 2006) for both Rev. G and Rev. F. Since most older towers were installed during Rev. F or older. However the analysis done for Rev. F would show that the tower is adequate for Rev. F. and may not be suitable for the owner, city, county etc. if they want thier tower to be up to par with the latest standard. Its kind of one of those things where it might be grandfathered in possibly?

As for which one to use it would seem appropriate to use Rev. G, however we have noticed that several towers built prior to 2006 were very close to their design limits using Rev. G and no room for additional loading. This would then require the owner to modify or reinforce the tower if they plan to install additional antennas/etc. to comply with Rev. G.

Our company uses RISATOWER which formally was ERITOWER. The original author of ERITOWER has since passed several years ago and [RISA] has taken over the software now called RISATOWER (from what we undertand). We have tried other programs (guymast) but have found RISATOWER to be the most appropriate program for our field.

So to answer your question - Use Rev. G.

 

[dmx]

Thanks for all the help....very useful information.