Permanent Installation of Road Ramp for Water Main

[wdl836]

I'll start with this -

http://www.globalpump.com/road-ramps.php

- so everyone knows what I'm discussing.

Has anyone ever seen this permanently installed in an active water distribution system?

The purpose is not the have vehicular traffic continuously cross a water main. I have a situation where we have a 20" water main and the need to cross the water main with a very large box culvert. From a stormwater hydraulics standpoint, I don't want to route the water main through the box culvert. The local municipality doesn't want the main 20'+ deep. The only real option is to go over the box culvert. However, going over the culvert will provide zero cover over the main, and will actually be exposed above ground. I'm already strapping the standard circular pipe to the box culvert. I was thinking that I may be able to install something similar to the previously referenced Road Ramp and secure it to the culvert, I could at least get enough cover to get a little grass to grow and not create an "eye sore" for the public.

Thanks for any insight.

 

[bimr]

There is no "easy" solution to a problem like this. You don't mention vehicular traffic, is traffic required?

Don't think the temporary structure will help.

Develop some options:

1 Detour around the obstacle

2. Go under.

3. Go over. There are plenty of pipe bridges. Some can be heat traced and insulated, some do not need it.

http://www.dhf.co.jp/eng/products/transport/bridge.html

Develop some options and let your client pick one.

 

[rconner]

Your inquiry and the apparent pipe/crossing gizmo you have provided link to are some innovative thinking (I assume they mean angled instead of "anged" in the fifth bullet of their ad blurb). Perhaps like bimr however I share some concerns with such at least some "permanent" application. E.g. if the proposed application is as it appears for potable water contact/conveyance and additionally in the USA, the conveyance must by law or regulation be listed/certified per NSF61 potable water contact standard effective in now virtually all states (and I don't happen to see such bullet feature in the ad, and for that matter don't know exactly how NSF would look at/test such a device?) Also, it seems like any traffic/impact involved could be directly and perhaps even somewhat unusually transmitted or transferred pretty much directly (little or no Boussinesq-like soil protection/cushion) to the device as well as directly attached/underlying culvert/conduit.
That being said, designs of structures combining even significant traffic carrying conveyance ability with conduit functions are not without at least historic precedent. An interesting visual illustration of such are the twin 48" cast iron pipe arch columns depicted in the historical photograph (image 123 of 507 this collection) at

http://www.militaryhistoryphotos.co...nn. Ave., carrying Washington Aqueduct..html.

This 200 ft+ span bridge was designed by General Montgomery Meigs of the U.S. War Department (later US Army Corps of Engineers) before the Civil War, and I believe Mr. Meigs incidentally also designed our near equally durable U.S. capitol dome using arched cast iron). This photograph from the National Archives was incidentally taken by a gentleman named Matthew Brady around the late 1850's, who was later to take many historical photographs including a few of the then quite lively President Abraham Lincoln. I believe these unique arches carried the structure, as well as all traffic up to street car on a little thoroughfare called Pennsylvania Avenue (and at the same time conveyed water under pressure of the Washington Aqueduct) for 50 or 60 years thereafter, at which time they were surrounded by a more modern and larger concrete bridge structure). I incidentally believe these particular pipelines are still in service today, now a sesquicentury later.
All have a good weekend!

 

[Pump2005]

Where I live the county is replacing a bridge over a creek on one of their roads. The bridge currently holds our water interconnection between the towns on each side as well as a force sewer main and natural gas transmission line. Since the bridge has small marinas on each side the bridge is being raised in height and in width for vehicle and pedestrian traffic. Now with the change in height the utilities would be 20' underground at the ramps and totally inaccessible if a repair is needed. The plan they settled on was to move all the utilities out of the roadway and underneath the creek. I don't know how far under in the creek but it also limits repairing damage in that area.

 

[gbam]

First, is there a way to reduce the box culvert height to provide at least 2-feet cover for your main or even add a concrete cap to the pipe to redistribute loads to outside of the pipe? Try and have your drainage guy change the culvert design to allow placement of the pipe.

 

[gerhardl]

Keep it simple:
1. Use standard watermains allowed for potable water to cross the river to get simplest possible operational and maintenance cost.
2. Contact a (landscaping?) architect to get ideas on an ethical, modern design for the extra necessary bearing and protecting structure. It need not necessarily cost a fortune.
3. For engineering purposes: check strength and structural needs, protection against climatic and general surrounding conditions. Include in discussions above.

Good Luck!