It will be a miracle if there are not substantial losses under the roof collapse at the B&O Museum. A big piece of roof, loaded with snow, coming down all at once, and dropping from that height, will produce the kind of forces that can flatten boilers, and bend axles, not to mention everything short of that. As bad as it is, it comes with a great blessing that a crowd of people were not under that roof, which I presume is often the case.

The larger question in my mind is the reason for the collapse. While tornadoes and hurricanes can knock down any building without warning, snow loads are anticipated in the structural design. Those design loadings usually far exceed any amount of snow that would fall in just one storm. If there are successive snowfalls that accumulate to the point of reaching the design limit, it must be removed with the same kind of urgency that is spawned by the outbreak of fire, for instance. The usual reason for a roof to collapse from a snow load is that the roof has structurally deteriorated. Is this present snow load the greatest amount that has ever been on that roof? Has there ever been any concern over the snow loading on that roof prior to this point? Has there ever been any limited structural failure in that roof, due to previous snow loads? Does that roof date to the origin of the building? While hoping for the best, I am very interested in learning why this happened.

Ron Keagle

KEAGLEDESIGN@VISI.COM

It is my understanding that this type of roof was designed to melt snow with internal heat. In the pictures you see a very sharp slope up to the center structure, since heat rises it will ascend along the wooden part of the roof and take care of the snow.

Apparently it was not warm enough inside the building last night so this feature did not work. I guess in the old days they might have idled a few steam engines to keep the temperature up when heavy snow was expected but sadly ancient steamers on static display don't generate much heat.

jus10ws@hotmail.com

Let's face one fact:

By the time of the roof collapse, the snowfall had (just barely) shattered the snowfall mark of the second-deepest recorded snowfall this century (February 1983) and was on the way to shattering the all-time record single snowfall for this area, set (if I remember the TV trivia correctly) sometime in the 1920s.

This is NOT a trivial amount of snow.

In addition, unlike some "monster" snowfalls that dump lots of thick (read: fluffy) snow, this snowfall began about midnight on the morning of the 16th and continued at the rate of an inch or two AN HOUR of FINE, HEAVY snow for 24 hours straight in temperatures of 10 to 20 degrees F--atop a couple inches of snow left over from the previous snowfalls late last week.

Buildings do have their designed capacity and life expectancy built in. It's obvious that this building has been in use for far longer than it was intended when built, and finally got a snowfall capable of breaking its aged back. Consider as well that nearly every rowhouse in the B&O Museum neighborhood has been in existence far longer than its designed life expectancy--which is why so many of them are falling down, condemned, or abandoned.

lner4472@bcpl.net

Not to mention that it was built to service cars and not hot steam locomotives anyhow.

It could be a truly beautiful old neighborhood no matter the age of the structures. I had been led to believe that the crime statics relating to the current indigenous population was the problem.

How many of us don't work or live or both in or on structures that have long outlived their expected life span?

Food for thought - this museum wasn't marginal about maintaining their place of business either. few of the rest of us can make that claim. How much more vulnerable might the rest of us be to a less intensive structural load?

Dave

> Not to mention that it was built to service
> cars and not hot steam locomotives anyhow.

> It could be a truly beautiful old
> neighborhood no matter the age of the
> structures. I had been led to believe that
> the crime statics relating to the current
> indigenous population was the problem.

> How many of us don't work or live or both in
> or on structures that have long outlived
> their expected life span?

> Food for thought - this museum wasn't
> marginal about maintaining their place of
> business either. few of the rest of us can
> make that claim. How much more vulnerable
> might the rest of us be to a less intensive
> structural load?

> Dave
My house is 163 years old this year. In the past 5 years the rebuilding I've done has been done with an eye towards another 150 plus years. I'm not saying this to take anything from the tradgey of this event, but I am hopeing all the roof work I did will prevent me from wakeing up to this type of problem. I insullated real well and the snow doesn't melt.
The other thing I'm wondering is if me and my crews can do anything to help, we are currently restoring B & O 6604 and hoped to send it to the fair. I'm waiting to find out if there is something we can do to help.

irss@eriecoast.com

> The larger question in my mind is the reason
> for the collapse.

Ron--

You are right to state that snowloading was certainly anticipated in the design of the building. But it's my understanding that the trusses, or at least the joint fittings of the trusses, are cast iron. As anyone who has worked with cast iron knows, it is notoriously unpredicatable, and it fatigues and eventually fails.

This is (to my understanding) why Cumbres & Toltec takes engines across their bridges singly. They're cast iron, and every loading cycle fatigues the metal. Eventually, it will fail.

It may be that the roof was perfectly ok the last time this much snow fell. But things could have happened in the interim to change that. A cast iron member might have finally had one to many load cycles due to wind, and once the first once goes, the rest are overloaded and it goes like dominoes.

I'm not a structural engineer, but that's my take...

Please GIVE GENEROUSLY, IMMEDIATELY!


https://www.borail.org/donation.asp

As we all know the museum was able to come back from this major disaster. Perhaps a lesser known result; is that the Northwestern Pacific Railroad Historical Society was given a number of iron parts, including the trucks from one of the crushed passenger cars.

The NWP people are therefore restoring the body of Central Pacific #29 later NWP 123 with Wason Car Company parts from 1869, the same year as their body.

The #29 is the fourth car body that the NWP volunteers have restored: two cabooses and a baggage car, now a full passenger car. After many years of being a paper society they have jumped into car preservation in a big way!

And that is not all! In their newly expanded Archives building, the NWP people have found some extremely valuable photos of the NWP #6101 baggage caboose that is being restored by the Society for the Preservation of Carter Brothers Railroad Resources. They are all doing good work!

Ted Miles, narrow gauge fan

3