Snow/Ice Melting Device for Ramps?

Most helpful. Thanks

Another choice would be embedded PEX tubing with warm propylene glycol circulated in it. Usually this can be heated more economically than with electrical resistance.

or move to Miami

It seems to be a valid alternative. Thanks

Thanks for your answer. Any company recommendation in the field of PEX tubing? Regards

Dishwasher salt.

Hot, rolling, aluminum cylinder. It's faster than a hollow one.

Is electric power available?

And cellular concrete is a good insulator, so buried pipes may not be the best answer.

Electric power is available. It needs to be of low voltage for safety considerations. The system should not create sparks in case fuel is spilled on the ramp. You got a valid point with cellular concrete being a good insulator. On the other hand the system shall be "on" 24 hours a day in winter. This might defeat the insulation barrier. What do you think? Thanks.

A few local kids in need of pocket money, equipped with shovels, brushes etc.

Good point! Please see clarification #16

Don't know, but you have my sympathy if you have snow/ice 12 months a year!

Seriously, where is this located?

You might want to look up technology related to heated driveways for a start.

Any place that gets snow 12 months a year must be pretty cold year round. McMurdo or Vostok? Dig out from under them and put a boiler there.

Now that you got them heated to melt the ice and snow. What you going to do when the permafrost melts and the docks start to sink in.

I always hated going back to class after cutting class the day before and find out I missed out on some really important notes that day!

Our local hospital uses overhead gas fired radiant heaters to keep the ambulance ramps clear. Catalytic converters,, they glow red and radiate large quantities of infrared downwards, three heaters cover a ramp of about 30 meters.

Welcome to CR4 chrissaki.

Just a note: should you go with an embedded electric system, in critical areas linear heating elements are to be preferred over mat-type layouts. Why? Should a mat fail, the entire area the mat serves will freeze-over whereas when you run linear elements in parallel and an element fails, the affected area is greatly reduced whilst also being far less costly to repair. If the inter-element spacing is not too great the adjacent elements will help to share the burden meanwhile.

To repair a linear section you would typically cut a groove into the surface at the operating depth using one of these:

Then, lay-in a new element, wire it into the circuit - in many cases running parallel to the edge of the ramp or driveway (picture a ladder where the rungs are the heating elements) test it and, if all is well, seal it in. You can also lay the linear element in a spiral or serpentine pattern, or use a mat. This reduces the number of circuit connections whilst increasing the risk of a failure affecting a larger area and being more expensive and time-consuming to repair.

If it is critical that an area remain snow-free 24/7/365, go with parallel linear elements in that area.

If it is absolutely 'mission critical' that an area remain free of snow at all times, lay-in redundant elements to keep downtime to a bare minimum.

For non-critical rectangular areas, go with embedded mats. For non-critical oddly-shaped areas, serpentine and spiral layouts allow more flexibility in placement.

Note: as these systems typically require between 500 to 600 W/m², you may wish to consider heating only the parts of your ramps which you expect to support the bulk of the traffic (the center of a driveway, for example, is seldom traversed, so why heat it?)

I would point-out that surface mats are subject to wear. For foot traffic they tend to pose a slight safety hazard.

Hope this helps.

-- If you're in northern Alaska (as ozzb suggests) then your chief problem is temperature. In that case, you might consider that they use ice roads up there, and perhaps you should define your problem as one of traction, not snow-and-ice removal. Baxterm mentions a radiant solution that operates from an overhead location. Do you have any overhead structures at your site already?

-- How heavy is the wear on these ramps? (Vehicle traffic or pedestrians?) What's your climate? Snowy or cold or both? What resources do you have "lying around" if any? Are there any nearby hydronic systems that can be tapped into? What about other waste heat from facilities, and what form is it in? Is your local electricity cheap? Are the ramps south facing or north facing? This can affect your calculations regarding cheap-installation-high-energy costs versus high-installation-cheap-installation costs.

-- How large are the "large areas" you mention? Are you talking areas that are large with respect to pedestrian traffic, or areas large with respect to aircraft traffic? Look around you and assess all relevant circumstances. Then describe your problem.

-- My tendency is to assume that "large areas" means larger than short driveways, and that you're talking on a big enough scale to justify some serious installation costs. (Yet your consideration of surface mats suggests a smaller area, since their deployment would be prohibitive otherwise.)

-- The odds of population distribution make it more likely that you're in a temperate climate, and that your needs are intermittent and not extraordinary. So shooting from the hip, see if you have any hydronic capacity nearby, and if it's sufficient to support the added load, or could be modified for reasonable cost. If so, go with a built-in PEX system. If not, evaluate a new hydronic system versus an electrical one (keeping local utility costs in mind).

-- There's too little information here. My head hurts. More information please.

Forgot to clarify that those ramps are not located in any particular country. It is meant to be a standardized construction to be installed at any geographical location.

The ramp is located adjacently to highways and meant to serve as arresting beds for heavy haul trucks veering off during an accident. This means that they will be used rarely and that they are expected to be damaged when an accident does happen. Costs are of secondary importance. Safety is the main consideration. The area could be as large as 2,500 m2 or 25,000 square feet.

Electricity is available but no nearby hydronic systems. Thanks

Here in the US Appalachian mountain highways I drive the "runaway truck" ramps look like they are paved with loose, deep gravel, maybe sand, with small hills built up over bumper height. I've always assumed that was to collapse under the truck and allow the wheels to embed and help deceleration.

Is that what you are speaking of? Why would you need to keep that free of snow?

Maybe in order for these ramps to function correctly, they must give way, and if frozen solid, they will maybe not stop the truck in time (or distance).

Forgot to clarify that those ramps are not located in any particular country. It is meant to be a standardized construction to be installed at any geographical location. Thanks.

Right you are! What I am trying to do is consider the possibilities and the options available today. Overhead systems are out of the question. If I know what options are offered, then I could propose the most suitable one in each case. Thanks.

OK, one thing that I've seen designers forget with snow melting surfaces is where does the melt go? At the bottom of your clean, dry ramps might be the worst case of black ice. Relying on drains that might become packed with snow could fail.

My point is that a good winter design should allow people to respond to winter weather conditions. Trying to predict every scenario everywhere will more likely fail somewhere at some time.

There is provision for water to flow freely off the surface and drain away following the inclination.

"....Overhead systems are out of the question...."

Is this because overhead systems have been expressly forbidden, or is there some design restriction that leads you to that conclusion? I realize you said expense is of secondary importance, but it is still of importance. Both long term and short term, covering the ramp to keep the ice off may be less expensive.

Don't forget we are out in the open air. Besides an overhead system presents a collision hazard

We are thinking of different overhead systems. I'm thinking along the lines of flexible tall hoops with break-away anchors that support a tarp. Consider filling the interior of the space with a number of thin membrane large balloons that would easily be ruptured by a truck using such a ramp.

Global Warming and your worries are over.

Some of the heat source you need has been successfully 'pulled' from the Earth Coupling of various vertical (to ~ 500ft) or horizontal (~ 12 to 8ft depths) drilled boreholes having pipe and grout installed for recirculated fluids/antifreeze, etc.

Earth as a heat Sink: Noted for on-going process cooling successes in sustainables (vs winders) , pipes in the ground , there as a heat sink, of common ployethelene sdr11 160 psi PE3408 are for the past 50 years still successfully used

Earth as a Heat Source: for your application IF FITTING, then heat exchange would be as a very simple (not easily done, but in expensive) heat source of 150,00 to 200,000 btuh per pump motor horsepower.

AN IMPORTANT NOTE IS INTERNAL PE pipe FLUIDS BELOW 28f START PUSHING FROZEN DIRT AWAY FROM THE GROUND COUPLED PIPING WALLS ON 1" and 3/4" DR11 POLY in contact with the ground conditions in 50f to55f earth that drops in temps to below freezing near the buried lines used for a source of heat.

~sometimes dramatically inexpensive in relation to a FREE heat exchange less costs and maintenance (little) of pumping circulated fluids, water, oils, antifreeze'd, etc.

Bridges are ice-melted, for many years, with circulated ocean water through in-laid tubing, one can research.

If local engineers are among those aware of the 40f to 70f ground conditions and use of the poly pipe for as a heat source, then they MAY be reasonably useful.

LOCAL GEOTHERMAL HEAT PUMP INSTALLERS, DRILLERS, LOOPER'S AND Oaklahoma State: IGSHPA AND THE GEO CONSORTIUM (one can search) has many years of data available.

a couple things seen :

In drive spacing with boiler-heated fluid in "pex" tubing in concrete that was 16" apart, in an icey Canadian drive, left 2" to 3" ice ridges between melted places, and ~ 5f day there.

An expert in Cleveland Ohio is a Mr jim Armstrong once/still? with Peerless mfg reps, and his typical 10" spacing- placements of tubing in all kinds of concrete, not more than 4" deep for the most, insulated sub-base designed, work nicely in -15f peaks usual -5f below zero winters, not with any permafrost, though... (pls contact your paid-engineer as red indicates). There are very many experts in radiant ice melting all over the world.

Seems more northern Canadian, and the like, applications solve this year round as so many already do.

~

Using as much PRACTICAL ground source loop technology for part of the heat exchange may result in over 200,000 btuh per circulation horsepower, IF THAT IS FIT for the application of just some of the ice melting.

http://cr4.globalspec.com/blogentry/23958

The problem can be solved without any high tech or heating, however you do not give sufficient detail.

Is this for vehicles or pedestrian?

Is it used constantly in both directions?

How long and wide is it?

Does it curve?

Is this a seasonal occurrence or is it a permanent requirement?

My first thought would be a floor covering that is hinged on one side that tips the snow off when opened and closes after use. To be left vertically when no snow or ice are threatened.

Can it be within a tunnel?

Can it be longer thus making less slope?

The installation of heat to solve the problem seems expensive and OTT.

The suitable answer can only be proposed when all facts are available.

Good Luck.

Energy Hunter.

Forgot to clarify that those ramps are not located in any particular country. It is meant to be a standardized construction to be installed at any geographical location.

The ramp is located adjacently to highways and meant to serve as arresting beds for heavy haul trucks veering off during an accident. This means that they will be used rarely and that they are expected to be damaged when an accident does happen. Costs are of secondary importance. Safety is the main consideration. The area could be as large as 2,500 m2 or 25,000 square feet.

Electricity is available but no nearby hydronic systems. Thanks

As the details come slowly in, the scenario dramatically changes.

Ice is your major problem not snow. Loose snow on the ramp will slow down your runaway vehicle along with the change in elevation and possible designed crumbling of a thin concrete into a soft subsurface. Packed snow from plows might act like a barrier but are out of your design control. Melting the snow to make ice somewhere else may cause the runaway from missing the ramp. Ice could also prevent your thin concrete from crumbling.

IMHO do not try to melt the snow on these ramps. The refreeze will make more problems than the melt will solve.

Having read your posts, and the replies thus far, I will now weigh in.

You want the most economic system that can be had. Why not simply use waste oil burners to heat a loop that runs under these escape ramps, but deep enough that there is not a chance of breaking the hot loop when the ramp is used? Any time the ambient temperature is at 1 °C or below, have the burners come on, and by the way, you could use a propylene glycol solution without posing a serious environmental problem in case the system fails and leaks. Other fluids would most likely be oils that would never, ever freeze, but you have to use the data on viscosity with temperature to see if a given thermal fluid is suitable in all locations. You want a sure fire ignition system, recommendation there is for an electric ignitor, but the power supply for it must include batteries rated for arctic conditions.

Aren't runaway ramps usually made of gravel?

No. Engineered materials arrestor system - Wikipedia, the free ...

Runway or runaway?

Runaway, off the end of a runway.

Yes, gravel is used here in the USA as well on roadways, maybe some airports too.

See post 28.

Usually sand in the UK - and we call them "escape lanes".

I think your right. This guy is still in school and his professor gave them an exercise to design an arrestor system. So what better place to come to and have someone else do our homework for you?

Oh NO!

You are right.

This guy may be a total loser who is trying to get us to do his homework.

Mileage Left in Used Engine Oil "I have been assigned by the professor of my engineering class to research practical ways"

chrissaki, tell us. Are you a fraud, or not.

I am 70 years old. I am addressing the CR4 community with politeness and respect. I have not insulted or obliged anyone to reply. This is a real and genuine project I am personally involved into. Your technical savvy and advice is valuable to me. If you elect not to be helpful, it is still OK with me. But politeness and respect have to be mutual. Thanks. Chris

Fine, then. I believe that you have, and will, get help with the project.

If you had been doing homework, it would have been a disincentive for some here to help you.

As someone has already said, there are many different environments where these ramps may go.

Different solutions may be needed for different locations.

Tanks, buried below ground where it never freezes, and recirculation pumps may also be an option. These could be controlled with temperature or ice sensors to only run when needed.

Heat pipes: Heat pipe - Wikipedia, the free encyclopedia may be an option in some areas.

These are used (in reverse application to yours) to keep the tundra frozen under the hot Alaska Pipeline.

How U understand heat pipes there at your link , and not the example - sold and installed since 1996 to industrial process cooling, in "Sutainables-site" Ground Loops , winders, etc? you are a surprise, again, but I have learned other lots from yuz , bud.

Your use of the English language makes no sense, causing a loss of credibility. Which is no surprise.

Right you are. The two threads are related.

Perhaps the real problem is drainage, not melting. Fluffy snow, and even a lot of snow that might melt on top and refreeze into a crust, isn't often going to be a problem when the issue is to slow down runaway trucks. The traction problem is a matter of liquid/melted precipitation that freezes and turns into slippery ice. If the drainage is excellent (not merely good), then what melts has a better chance of being removed from the situation, and the freezing problem is limited. Someone above mentioned that sand is used in the UK. But sand doesn't drain fast enough, and when wet, can freeze eonugh to prevent the efficient stopping of a truck near the Arctic Circle.

-- The runaway truck ramps that I've seen in the U.S. mostly use fairly large aggregate, say 3/4" or more. I would suggest that the colder the climate, the larger the aggregate (within reason). Larger aggregate has less in the way of ice-bonding surface area, and is less likely to form a rigid structure in the presence of thaw-freeze cycles. I haven't done the homework on this, and there may be circumstances where moderately-sized aggregate may freeze up too much (lots of precipitation and lots of thaw-freeze cycles with quick onsets), but my intuition is that 1-1/2 aggregate is about as large as could be required.

//www.mainroads.wa.gov.au/BuildingRoads/StandardsTechnical/RoadandTrafficEngineering/RoadsideItems/Pages/Design_of_Truck_Arrester_Beds.aspx#.U5Ol2PmSxrY

On the outside chance that you are not a student (but the naivete of the question and the dearth of data indicate otherwise), I do not see how there can be a "one size fits all" solution since local conditions and codes will govern or limit your choices.

And don't forget the energy costs, at 50 watts/ft² 24x7x365 you're going to blow through nearly 440kWh per sq ft per yr., on a 200 ft x 15ft ramp that's a 1,320MWHrs per yr, hardly a "green" project, and I can just imagine what happens when the local wildlife finds this as a comfy place to winter out.

what about placing a roof on top of the ramp?

The application? Would a few of these installed overhead and switched on as required
be helpful? Cheap, not expensive, can be used as and when required, easily re-positioned
when necessary, and easily replaced when faulty. jt. Or, rock salt?

Now you tell us more about the "application," is a ramp really necessary?

Would it be more likely to help overturn a large truck out of control?
In which case a well drained large sand pit verge would seem the best solution?
(problem is, you cannot sell these! )

Are you trying to create a salable product for a problem already solved?

jt.

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