[AT] OT Low water crossings
Carl Gogol
cgogol at twcny.rr.com
Sat Feb 11 06:13:43 PST 2012
I understand you now, Charlie
In these situations it always comes down to what materials and equipment are
readily available / cheap. Use what you have and minimize the overall
needs. That strategy seems to be in play Low water crossing have a real
advantage in that you basically install the pipes at an existing flat grade.
If there is little height involved in the created barrier, there is little
pressure to force water under the culverts. Low barrier height means small
diameter pipes but that leads to an easier tendency to plug. Here it is a
compromise on how much effort is required to install the pipe and how likely
it is to fill with trash. I have one crossing that uses a 10" pipe with
zero over cover. I had #2 stone available and a couple of buckets were used
to make it easy to climb over the pipe. I has access to a number of
(seconds) concrete parking lot stop barriers and just used 4 of them to
create wings. I have not had issues with washout in over 5 years. It has
actually surprised me. It is soft and the weight of vehicles crossing has
required a few pails of stone to level the wheel tracks every few years.
This is in a large wash area and when flooded the water probably doesn't
exceed 5 MPH.
-----Original Message-----
From: charlie hill
Sent: Friday, February 10, 2012 4:35 PM
To: Antique tractor email discussion group
Subject: Re: [AT] OT Low water crossings
YEP!
-----Original Message-----
From: Dave Merchant
Sent: Friday, February 10, 2012 2:55 PM
To: Antique tractor email discussion group
Subject: Re: [AT] OT Low water crossings
Reminds me of this video...
http://www.youtube.com/profile?user=SteamCrane#p/f/27/wyVIVHJ5RUA
Real time!
Dave Merchant
At 01:28 PM 2/10/2012, you wrote:
>Carl that is why I said to put head walls or wing walls off the end of the
>pipe. I guess I didn't explain well enough. He needs a bulkhead on each
>end of the pipe then fill in the middle and concrete over the top. It's
>perfectly fine to do the whole thing with concrete but concrete isn't cheap
>and unless you seal the ends down into the stream bed the water will still
>get under and either undermine or lift the slab. The idea is to make the
>water flow over the entire structure and hold it down. Yes, the fill must
>be compacted tight and contained. Head walls would be straight and
>parallel to the road. Wing walls would angle out into the earth along side
>the stream at an angle to the stream and the road. Probably the easiest
>way to do it is with bags of concrete mix. Stack them like sand bags
>around
>either end of the pipe, drive rebar through them and into the ground.
>Spray
>them down with water and leave them be for a few days until the concrete
>gets hard. Then form the roadway between them with concrete or a
>combination of fill and concrete. The concrete bags at the bottom of the
>stack need to be dug down into the ground on either side of the stream
>until
>the bottom of the trench is level with or slightly below the invert (bottom
>of) the ditch/creek.
>
>There are dozens of ways to do it. Admittedly, in my construction career I
>was generally doing such work with other people's money and they were
>usually companies that could afford to and required
>us to do it right. That doesn't mean there isn't an easier way to do it
>that would be serviceable. I just don't like to build something twice.
>
>Charlie
>
>-----Original Message-----
>From: Carl Gogol
>Sent: Friday, February 10, 2012 12:48 PM
>To: Antique tractor email discussion group
>Subject: Re: [AT] OT Low water crossings
>
>In this application there is a high probability of compacted fill washing
>out as the design intent is to allow very high water levels to still go
>over
>the top - isn't it?
>
>-----Original Message-----
>From: charlie hill
>Sent: Friday, February 10, 2012 7:45 AM
>To: Antique tractor email discussion group
>Subject: Re: [AT] OT Low water crossings
>
>
>
>Don, I can't really help you other than to say that if you use a culvert
>made for road crossings the manufacturer should be able to tell you how
>much cover it requires for a given load. Dirt is cheaper than concrete.
>Depending on the circumstance I'd be looking at building a "head wall" or
>"wing wall" of the ends of the culvert. That could be wood timbers,
>concrete, stacked bags of concrete mix, sand bags, rip rap or a number of
>things.
>Then with the culvert set in place I'd want an appropriate amount of
>compacted fill on top as Cecil suggested. You can cut down on the amount
>of
>fill required (the depth of the fill) by using geotextile fabric (see this
>site http://geotextile.com/downloads/PropexLL507.pdf for an example).
>If there is a road contractor near you he might have a small amount on the
>end of a roll, a remnant, you can get to do your job. When all that
>is done you can pave the road surface with 4 to 6" of concrete depending on
>how well your subsurface is compacted and gross weight of vehicles
>you expect to come down your road.
>
>Someone spoke about the strength of concrete. That is true. You can get
>concrete with compressive strength generally from 2500 psi to 5000 psi.
>However, the concrete that is used on highways and runways is typically
>classified by flexural strength rather than compressive strength. The
>difference is that the "flex" concrete has a high amount of "entrained air"
>(air bubbles in it) to allow the concrete to flex under the load. That
>concrete
>is typically classified by terms like 450 Flex or 550 flex. With all that
>said I don't think that is anything you need to concern yourself with. For
>what you are doing I'd probably use something like 4000 psi concrete with
>fiber added and I'd have them mix it dry and add plasticizer to make it
>flow
>easier with a lower water content.
>
>That's about the best my memory will allow. If your local concrete yard
>only handles driveways and house footings they might not even know about
>"flex"
>concrete anyway. Oh, as for the added fiber, you can get that now as
>fiberglass fiber or a sort of plastic fiber. I've never used the new
>plastic fiber but I hear it
>works well. The fiberglass fiber is tough stuff and helps reduce cracking.
>It also cuts down on or eliminates the amount of reinforcing wire mesh or
>rebar you need to use in the
>concrete.
>
>Hope that helps some.
>
>Charlie
>
>
>
>
>On Thu, Feb 9, 2012 at 5:20 PM, Don Bowen <don.bowen at earthlink.net> wrote:
> > My driveway crosses two little creeks. They are usually dry except
> > during storms when they can be as much as four feet deep. After a storm
> > it may take days for them to come down. The first crossing is gravel
> > and the previous owner had build a concrete and rock dam on the
> > downstream side to control washouts. The result kept the water over a
> > foot deep for days after a small rain. I cut a slot in the dam and now
> > it drains down to about 6 inches in a day.
> >
> > The second crossing is a concrete low water bridge with two culverts.
> > usually within a few hours of a rain the water is under the concrete
> > flowing though the culverts. The problem here is that the culverts plug
> > with gravel in heavy rains. The reason is that who ever built the
> > crossing has the outlet end of the culverts higher than the inlet by
> > several inches.
> >
> > I plan to take out the culverts and replace them with a single larger
> > culvert properly installed. What I need to know is how thick the
> > concrete must be above a given size of pipe. I am assuming that the
> > larger the culvert diameter the thicker the slab over it must me.
> >
> > As for the gravel crossing I want to build a concrete crossing. I need
> > to know what I need to do and references. I have a good idea what is
> > needed but I would like comments from those with experience.
> >
> > You can see in this picture the right culvert is plugged. The water at
> > the inlet is almost at the top of the culvert.
> > http://www.braingarage.com/Dons/Travels/journal/May%2011/images/flowing.jpg
> >
> > This is what it looks like after a heavy rain.
> >
> http://www.braingarage.com/Dons/Travels/journal/April%2011/images/flooded%20drive.jpg
> >
> > And a heavier rain.
> >
> http://www.braingarage.com/Dons/Travels/journal/April%2011/images/flooded%20drive.jpg
> >
> > The gravel crossing after a rain before I opened up the dam a
> >
> little\http://www.braingarage.com/Dons/Travels/journal/January%2011/images/summer.jpg
> >
> >
> > --
> > Don Bowen KI6DIU
> > http://www.braingarage.com/Dons/Travels/journal/Journal.html
> >
> > _______________________________________________
> > AT mailing list
> > http://www.antique-tractor.com/mailman/listinfo/at
>
>_______________________________________________
>AT mailing list
>http://www.antique-tractor.com/mailman/listinfo/at
>
>_______________________________________________
>AT mailing list
>http://www.antique-tractor.com/mailman/listinfo/at
>
>_______________________________________________
>AT mailing list
>http://www.antique-tractor.com/mailman/listinfo/at
>
>_______________________________________________
>AT mailing list
>http://www.antique-tractor.com/mailman/listinfo/at
Dave Merchant
kosh at ncweb.com
kosh at nesys.com
dmerchant at layerzero.com
http://www.nesys.com
http://www.nesys.org
YouTube: SteamCrane
_______________________________________________
AT mailing list
http://www.antique-tractor.com/mailman/listinfo/at
_______________________________________________
AT mailing list
http://www.antique-tractor.com/mailman/listinfo/at
More information about the AT
mailing list