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Protecting Buildings from Train Car Explosions
4

Protecting Buildings from Train Car Explosions

Protecting Buildings from Train Car Explosions

(OP)
Link

Recently, a train car explosion wrought havoc in a community in Quebec, Canada (see link). Developers in my area are now wondering if steps should be taken to mitigate potential disasters of this sort (blast walls etc.). Is this common practice anywhere in North America? Have any of you provided train blast protection for any of your building projects? If so, I'd love to hear about it.

Thanks for the help.

KootK

RE: Protecting Buildings from Train Car Explosions

Not common practice. Too expensive - and would be very ugly having concrete blast walls all along tracks near buildings.

And the situation wasn't so much blast effects as a barreling train jumping the tracks. Not sure how you one could design screen walls to stop a train.

RE: Protecting Buildings from Train Car Explosions

If that's the case why don't we design all building to design for an atomic bomb impact. That's stupid legislation, it's a knee jerk reaction to a terrible tragedy.

I'm sure once your developers saw the costs of building to those kind of requirements they would change their tune.

Should buildings near chemical production facilities be designed for explosions?

How about that fireworks plant that exploded, same issue.

You design for what is a realistic situation. Otherwise why aren't all bus shelters designed to take a vehicle impact at full speed.

RE: Protecting Buildings from Train Car Explosions

(OP)
I am of a similar mindset. Still, I appreciate the the developer's efforts at due diligence.

RE: Protecting Buildings from Train Car Explosions

One reason not to have large populations next to rail lines that carry hazardous material.

Mike McCann
MMC Engineering

RE: Protecting Buildings from Train Car Explosions

It's all about risk and consequence. The reality is that these events are very rare and even then when something happens the consequence is usually relatively low in respect of the general public. This incident sounds much like the benefited explosion in that it shouldn't have happened according to most theories about that type of product, i.e. fire yes, but explosion, no.

Where you build walls or add extra cost needs very careful consideration or you're just wasting money for no decrease in risk. As cold hearted as it might appear, human life in terms of cost / risk impact has a value, somewhere about $5 million per life saved. However this is factored over many locations where incidents statistically won't happen so it doesn't take much extra cost in loss of places to add up to that. All hazardous substances have the same debate and issues, my experience comes from liquids and gas pipelines and the issues are similar, risk reduction versus cost.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

RE: Protecting Buildings from Train Car Explosions

That should have read Buncefield explosion.... Damn predictive text.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

RE: Protecting Buildings from Train Car Explosions

Well, the original train tracks not ony went from large town (dense, highly occupied area!) to large town (dense, highly occupied area!) but they were specifically laid out to go through as many small towns as possible on the way - because the trains WERE local and DID carry as much freight and passengers on their "local" runs as possible. At EVERY town along the track, the train station was as close to the center of town as possible, because that was where the people are, the cargo is, and where the transportation was needed. Is still needed.

Along the way, the tracks ran as short as possible, ran as flat as possible, crossed each valley, ridge, and river as short and flat and direct as possible: which IS the way the roads went - or if the tracks were going before the roads did (which also happened) then the roads parallel the train tracks because that was were the traffic and people wanted to go - as short, flat, and direct as possible works both ways.

The potential destruction by a [train wreck -> gas or chemical release - explosion] is real.

BUT the explosion release area (the safety area around a potential explosion) needs to be too large to be isolated to try to minimize hazards of potential explsoions. And, though multi-billion dollar "blast walls" (or a submerged track below ground level) might help if the blast were small enough, then the enviro impact would be another 10x billion dollars. Worse, any release of "gaseous" (explosive or toxic!) substances WILL NOT be contained by the blast walls. (A fire would not be contained either, though a fire by itself would not be as hazardous as a fire -> explosion combination. But the blast walls would not stop the fire -> explosion of a nearby train car. )

So the whole attempt is expensive, useless, and meaningless. But sounds good. To soebody who can make a name (or get money!) by "trying" to do something - which ends up useless and expensive by using somebody's else's moeny.

Which is why it is a typical government "investigation" by a nanny state for nanny-staters catering to nanny-stators.

RE: Protecting Buildings from Train Car Explosions

While working for a slurry wall company I did a cement bentonite ditch and sat precast panels where a train track ran under a rapid transit bridge so a derailment would not bring down the bridge. A long version would be cost prohibitive for the risk.

RE: Protecting Buildings from Train Car Explosions

It would be possible to provide some blast protection at modest cost >in some locations< by running the tracks inside a natural ravine or manmade 'cut', i.e. substantially below the elevation of the surroundings. It should also provide some reduction in airborne train noise within the surrounding community.

I'm not aware that cuts have ever been made for that reason.

Mike Halloran
Pembroke Pines, FL, USA

RE: Protecting Buildings from Train Car Explosions

I drive by the Dallas Convention Center on I-30, and there is a train track that actually runs under the building. Makes me curious how much thought went into that arrangement! See the Google maps view of it, attached.

In answer to the original inquiry, train explosions like that are fairly rare, but derailments are more common. Even if it's a unit coal train, the coal won't explode, but flying gondolas full of coal can wreak some havoc in the general vicinity of the track, and that would probably be a more worthwhile concern than explosions.

The way they handle this on US highways is that they have designated "Hazardous Cargo" routes, so theoretically, you shouldn't be driving your dynamite truck through downtown Dallas. The problem with railroads is, they don't have a lot of optional routes, and a lot of large towns sprung up specifically because the railroad was there.

RE: Protecting Buildings from Train Car Explosions

That is an electric light rail under the Dallas Convention Center. The freight rail is west of the buildings.

RE: Protecting Buildings from Train Car Explosions

Georgia World Congress Center/Georgia Dome/Atlanta Hawks arenas are overtop of the main rail line through downtown Atlanta.

RE: Protecting Buildings from Train Car Explosions

All those tracks coming out at the right are freight tracks, that's where I've seen freight trains coming through; that's visible from I-30 as you drive past. The top two lines on the left are Dart lines (note the electric lines and supports which distinguish them), where they come out of the building is not visible in the picture. If you go to the Google satellite images, you can see freight trains or cars on some of those lines farther to the southeast of the building.

RE: Protecting Buildings from Train Car Explosions

Since these accidents are all the railroads fault, the tank car’s fault, why not just put a 12 or 16" reinforced shell of concrete around all tanks on these cars. The explosions would be smaller too, because each car could only haul 50 gallons of fuel, and stay within weight limits. smile Alternatively, don’t build so close to the RR tracks, or pay to have the tracks moved to the other guy’s neighborhood. Of course, you couldn’t ship and receive product by rail any longer. When you think of the millions of ton/miles or gallon/miles which are shipped by rail, it is actually a pretty darn safe transportation system. Could they do better? Of course, but at what cost and who’s cost, and how much is enough? What are the alternatives, would you like to see that same volume coming at you in tanker trucks on a two lane road? There is always that same kind of knee-jerk reaction after any tragedy. I certainly am sympathetic with any people who are hurt by such accidents. Show these people what’s involved and what it will cost, and ask them how they want to pay for it. We all use the fuels being shipped, and would scream like hell if it cost another $1 a gallon.

RE: Protecting Buildings from Train Car Explosions

The Alamodome in San Antonio, Texas also has a freight line running next to it.

RE: Protecting Buildings from Train Car Explosions

"Whose money?" is always the polygon bounding the solution space to any problem.

Mike Halloran
Pembroke Pines, FL, USA

RE: Protecting Buildings from Train Car Explosions

Those rail cars were designed for very high flash point material, and were filled with considerably higher flash point material.

Choose the right rail cars for the load, and the hazard is greatly reduced. No concrete necessary.

RE: Protecting Buildings from Train Car Explosions

JRod12... knee jerk or not, the tragedy may have been avoided... there may have been a 'bucket full' of neglegence involved.

Dik

RE: Protecting Buildings from Train Car Explosions

I agree Dik. But does that mean we should be designing everything within a certain distance of the tracks for an explosion? Obviously not or else you live in a fantasy world where sexy women sweat money and are ridiculously attracted to nerds.

RE: Protecting Buildings from Train Car Explosions

A current buzzword with the FHWA is systemic safety. The idea is to determine which road geometry and traffic control conditions have the highest crash rates, such as sharp curves after long tangents, and treat them. They contrast this with systematic safety, or trying to treat the whole roadway system, or reactive safety improvements which are taken after crashes occur.

I'm not a railroad person, but I suspect this sort of systemic approach would be cheaper than lining all urban railrioads with blast walls. The FRA and equivalent agencies in other countries could look into derailments and determine what geometric design features and rail conditions tend to have frequent derailments, then fix those first. If for some reason, the geometry can't be fixed, then it might be a candidate for blast walls or whatever.

RE: Protecting Buildings from Train Car Explosions

Edit: the rail cars were designed for high flash point material (i.e. low volatility, few flammable vapours), but were filled with much lower flash point material (more volatile, more flammable vapours).

RE: Protecting Buildings from Train Car Explosions

Moltemetal, do you know something we don't?. I have been puzzled by this accident since I first heard it as it was always described a "crude oil". I don't know what type of crude is normally railed about in Canada, but if it was stabilised crude cooled after a long night on the train, it should not "explode" , like it clearly has. Burn yes, but not explode in an unconfined area.

Was there something else in the crude?, was there other fluids in the middle of this train?

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

RE: Protecting Buildings from Train Car Explosions

Why concrete blast walls?

Most of the explosive storage/handling sites I've been to relied more on earthen banks/berms/holes in the ground...

So, where the track isn't already in a cutting, then if feasible add berms which could also double for sound abatement etc.

However, most of the above comments still stand.

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RE: Protecting Buildings from Train Car Explosions

I'd think in snowy territory a wall or trench would tend to create snow drifts, increasing the likelihood of a derailment.

RE: Protecting Buildings from Train Car Explosions

Littleinch , I think that what Moltenmetal knows that you are apparently not aware of, is that according to reports in the Canadian media, the contents of the rail cars originated from the Bakken field in North Dakota. The gas produced from these fields is apparently quite wet with hi value condensates and the like. This I believe was what was being transported and yes, more than one individual has already remarked that to show the contents as crude oil on the manifests was less than accurate.

RE: Protecting Buildings from Train Car Explosions

Ah, that makes more sense. So what we had here was a train full of "condensate", that all encompassing word for some highly volatile stuff. No wonder it exploded.

Thanks for the info.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

RE: Protecting Buildings from Train Car Explosions

(OP)
Thanks for all the great discussion guys.

I'm now looking to assemble a list of significant projects that have trains running next to or beneath them. Or over them I suppose... I'd like to share the list with my client in order to increase their comfort level with the situation at hand. So far, thanks to this thread, I've got:

1) The Alamodome
2) The Dallas Convention Centre
3) The Georgia World Congress Centre

Can anyone help me expand my list?

Thanks again,

KootK

RE: Protecting Buildings from Train Car Explosions

KootK:
Almost every industrial area with railroad track running through it, particularly those with main line tracks, much switching and waiting/standing trains. Main line trackage from and to RR switching and sorting yards, very high traffic. Lines into and out of major industrial complexes such as refineries. Every major port and the neighborhoods around them. Los Angeles and its ports actually have an open-cut tunnel system of main line tracks which keeps the train traffic separated form the surface traffic and activity. As I said in my earlier post, ‘when you think of the millions of ton/miles or gallon/miles which are shipped by rail, it is actually a pretty darn safe transportation system.’ We have never really tried to do anything to contain this type of event; rather have improved safe train handling; improvements in tank car designs such as head shields, F-type couplers, valve and fittings protections, etc. I don’t think anyone has been able to justify the risk vs. cost of doing much more. Without a doubt, there may be a situation where someone would want to (be willing to) pay the cost to protect something they valued enough. And, I don’t mean to downplay the tragedy or significance, to the people immediately involved, when something like this happens. It’s just that you can’t afford to put every mile of RR track in an enclosed, explosion proof structure/tunnel. They do control the routing of nuclear waste, and the like, and the containers in which it is shipped. But, you could never afford to ship a bulk product that way.

RE: Protecting Buildings from Train Car Explosions

(OP)
Thanks dhengr. I agree that there are endless examples of railways next to buildings. I'm just trying to demonstrate to our design team that there lots of precedents for high profile public buildings next to railway lines.

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