Foundation designs for telecommunication towers

[paaz]

Hi,

I have been trying to find a sort of a guide to use a design software for Drilled Piers for Telecommunication Towers. The software is made by Powerline systems and it is call CAISSON. I am currently having difficulties trying to come up with suitable or workable foundation designs for such structures.

Anyone out there that have used this design program before or using it now and have some good tips I would gladly appreciate the help. I have been designing Monopoles for over 7 years, but foundation for such structures only for 4 months.

I thank you in advance for your help, and if this is not the right forum for this thread please advise which forum will be the most appropiate.

 

[miecz]

Forum 256. Also, check into LPile.

 

[paaz]

I tried to find forum 256 but could not. Could you post a link to it.

I thought about LPile, but we did not pruchase that program. We purchased CAISSON from Power Line Systems. I tried to ask questions to the folks at Power Line but was not succesfull.

I mean I know it must be fairly simple and just a matter of interpretting the soils report, but for a person that has never done so, it turns out it is not that simple. Hence the reason I am looking for some guidence other than the "manual" that Power Line provides with its softwares.

 

[miecz]

It's the Foundation Engineering Forum under Geotechnical Engineers.

 

[DMcGrath]

All the monopole foundation designs I saw came from the tower manufacturer, based on a boring log / geotech report that we supplied to them. The foundation design came as part of the "package" for buying their tower.

 

[csd72]

See if you can get your hands on the AASHTO standard specs for highway signs....

They have a section on single caisson(pier) foundations with charts to get depth of embedment.

 

[paaz]

jmiec----I will look under that particular forum. I will let you know how it came out. Thanks

DMcGrath---I know that the foundation designs comes from the tower supplir. I worked for a tower supplier before, but we never had to bother on supplying the foundation design. We outsourced that. Now that I work for a different tower supplier, aside from the Monopole design, I have to do a foundation design. here is where the problem is. I have no education on this other than reading the CAISSON Manual 4 months ago when I started this job. I just need a little more guidence on soils interpretations.

csd72----Thanks for the tip on The AASHTO std. I will try to get a hold of it as soon as I can. My company is not a great spender on books, but I am trying to build a library of engineering books directed to the design of towers.

 

[transmissiontowers]

I use Power line systems software for analyzing transmission towers and poles, but do not do the foundations. I believe in putting my mistakes up in the air where everyone can see them, not burying them in the ground.

We (our geotech's) do not use the Caisson software module and use either Lpile or a beam-column program that was done for us many years ago by a University of Houston professor Michael O'Neil.

Like most of the PLS software, they assume a through knowlege of the subject and do not have time to educate users with no experience.

_____________________________________
I have been called "A storehouse of worthless information" many times.

 

[paaz]

Transmissiontowers..... I believe on fixing my mistakes before they become real, and that is why I have post this thread, to get the understanding needed to use the CAISSON program.

 

[STR04]

Paaz,

I agree with Transmissiontower. Why put your neck on the line for any area not of your expertise? Spread the risk around to someone else and hire an consultant. If you were a geotechnical engineer and fully understood how L-pile works, then plugging into a black box may be your thing. But I sure hope you didn't sell something to your client that you cannot deliver. Been there done that. Good luck with everything.

STR04

 

[paaz]

STR04, Thanks for your concern. Currently we outsource our foundation designs like many other tower vendors in the industry.

However, I would like to get familiar with the design of drilled pier foundations so I can strat designing some of those too.

For what I have read, LPile is the software to have. Apparently not a lot of, if not none, information regarding the CAISSON software from the Powerline people.

Thaks for all of the information, but I will continue my quest to find some expertise on CAISSON.

 

[transmissiontowers]

""I believe in putting my mistakes up in the air where everyone can see them, not burying them in the ground. ""

I meant the above quote in a joking manner and tell the geotechs at work this phrase when discussing engineering design. Sorry if you took it wrong.

On a constructive note, you might try eMailing Alain, Erik or Otto at PLS and ask where you might find more info and training on Caisson. I read thru the manual just now and it seems pretty straight forward. You input the pier loads, diameter, concrete strength, and the soil strata data which I guess is available from the soil boring report. The program determines the max shear and moment on the pier and gives you the number and size of rebar in a matrix to choose from. An example problem is included and the appendix has some references you can research.

I would start with a through reading of the manual and working of the example problem.


_____________________________________
I have been called "A storehouse of worthless information" many times.

 

[paaz]

Transmissiontowers---Itis a tough industry and trust me I have participated on other "So called Engineering forums" Nonne on Eng-Tips, on which people don't any good on helping.

Sorry about snapping.

Thanks for the tip. I've had contact with PLS folk before in the past when I used the PLS-Pole program on my previous job. I have read the manual for CAISSON, and it seems very simple, but when I input values frm previous jobs as comparisson, my results are close to those already done previously.

Thanks for the support, I will try to contact PLS and try to find out if there are any trainning sessions, or if they know of any other institution near my area that offers such sessions.

I must be doing something wrong and think that if there are some training courses on this I could understand where my mistakes are before I even atempt to officially start designing foundation for telecommunication towers

 

[transmissiontowers]

Take a look on their web site for training courses. There is one going on right now in Orlando, Fla on line and foundation design. Since you are in the telecom industry and do not need the line design part, you might see if they would allow you to only pay for and attend the day that they talk about Caisson. There is one later in the year in Madison, Wi.

_____________________________________
I have been called "A storehouse of worthless information" many times.