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Re: RR Tie retaining walls

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Kathleen A. O'Brien wrote:

> 1. Does anyone know how easy it would be to get RR ties and telephone
> poles?

Used RR ties are readily available in northern CA and landscape supply yards.
You should limit your spec to AA or "re-lay" grades, the kind railroads remove
from mainline service and resuse on spurs.  Lower grades are generally quite
deteriorated.  Poles are available from electrical supply houses, usually as
temporary power poles.  I won't use anything but "new" material for the poles.

> 2. Does anyone have any ideas on what allowable stresses would befor RR
> ties? I would probably assume stresses for redwood if I couldn't get any
> information.

The species of ties varies with the area of the country and can be fir, pine or
hardwood, all treated with creosote.  Since size is typically 7"x9" or larger
with a length of only 8-9 feet, a large section modulus is available and
stresses should not be a problem.  I believe that AAR (American Association of
Railroads) has a web page and a comprehensive set of standards.  Poles are
almost always a very good grade of doug fir, often first growth.  Check with
the engineering department at SoCal Edison for a spec.  You might also try
Baxter the treating company.

A word of caution.  Ties are treated with creosote, a Prop 65 material in CA.
I would not use them where people, particularly children could come in contact
with them.  I have inspected 70+ year old wood bridges where the creosote still
got all over myr clothes as I climbed around.