Transite Design Information

[jdonville]

I would greatly appreciate any engineering information for asbestos-containing TRANSITE pipe. I have a project where we need to cross a buried 24-inch TRANSITE sewer pipe with a heavy traffic load, and I want to compare the pressure against allowable limits.

Jeff

 

[rconner]

While your problem as described might actually involve more complicated design/considerations, I know there is an ANSI/AWWA C403 standard for the "Selection" of 18"-42" asbestos water pipe (that includes at least some design-related information). I think I can also remember other manuals over the years that might be more applicable to sewer or drainage pipes, if they were made differently with regard to classes etc. I suspect it would be most helpful to know quite a bit about the installed pipe, actual bedding, and present condition of the pipeline to analyze this thoroughly. This sort of pipe is of course known to be quite brittle, although larger pipes in general may be at least be a little more resistnt to damages than the smaller.

 

[jdonville]

rconner,

I am assuming that the utility that owns the pipe has a proper installation. Test boring information in the vicinity of the pipe suggests that the soils are low-blowcount uncontrolled fills to a significant depth.

What I don't have any idea about is the material properties of the Transite material itself, so I don't have a baseline to know when the stresses from the traffic loads (we will be traversing the pipe only twice) are sufficiently reduced, depending on the measures we undertake to spread out the loads.

We will have a 100-ton capacity crane potentially carrying a 80,000 ton load across the alignment of the pipe. Due to the dimensions of the crawler tracks, we already get a pretty good reduction in the ground pressures.

Based on the test boring information that we have, we will likely need to take measures to permit safe transit of the loaded crane on the fill soils anyway. What I would like to determine is how much more to do to protect the pipe from this loading.

Any further information or thoughts are appreciated.

Jeff

 

[RWF7437]

I have two Johns-Manville Installation Guides for Transite Ring Tite Pressure pipe dating from 1960 and 1969. These are probably no longer in print and J-M has gone bankrupt. Let me know if you 'd like photocopies. rwf7437 AT comcast DOT net.

As others have cautioned, this is old, possibly brittle stuff so be very careful.

Did you mean 80,000 tons or 80,000 pounds !?
good luck

 

[cvg]

take extreme caution with the transite! number 1 it is inherently brittle and number 2, broken pipe becomes hazardous waste. you may be better of replacing the pipe with a section of ductile iron before you cross it rather than repairing a leak. Or perhaps you can shut down the line to remove pressure during the crossing and then carefully pressurize it afterwards.

 

[rconner]

Even if whatever is considered proper/new properties for the pipe are present (and this may not be a given), the standard I referred to shows five different "beddings" for selection of asbestos water pipes, all with their own "load factor". The actual load factor achieved in the field is thus important(or critical?) to the safety factor (or lack thereof) of the rigid pipe in the transient event.

 

[greenone]

CVG-Normally asbestos waste is regulated waste, not hazardous waste. Landfills need to be permitted to accept it, so it cannot just go out with other scrap.

 

[cvg]

agreed, and in my case, that means hauling it about 500 miles to a landfill that will accept it and across state lines...

 

[BigH]

john - why not drive some timber piling (poles actually) straddling the pipe and put on a cement stabilized pad above - transferring the load below the pipe. Might be a quick and expediant way to do it - or use steel piles and recover them?

 

[dicksewerrat]

You will have to calculate the new live load on the pipe. Then probably design a new pipe in its place. Those loads are more than Cooper loading. More like runway loads. Is this pipe a pressure pipe or gravity?

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[jdonville]

All,

Whoops! I did mean 80,000 lb rather than tons. I appreciate the warnings about handling of the asbestos concrete. We will strive mightily to avoid damaging the pipe in the first place!

rwf7437,

I have sent you an email. Many thanks for your generous offer.

BigH,

Bridging the pipe with a purpose-built structure was one of my first thoughts, as well. Naturally, we wnat to keep the cost down, as the need to do this was not entirely forseen.

Jeff

 

[dicksewerrat]

80,000 lbs is just an HS-20 load. At 15 feet deep the load is about zero. 3 feet deep is a problem.

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[jdonville]

Richard,

We ended up excavating trenches parallel to the pipe and pouring plain concrete bents to bridge over using crane mats.

Jeff