Monorail Track Swaying/Rocking/Shaking?

[judino28]

Last week, while waiting for the monorail at the Grand Floridian station, my wife pointed out to me how much the monorail track beam in the station was swaying after a monorail had just gone through the station. Similarly, when our monorail approached, the track began to shake/sway again. And this was not just a little vibration, but visible movement of several inches side to side swaying/rocking.

I figure this must be normal, though I can't find any discussion of this anywhere. Has anyone else ever noticed this?

 

[Goofyernmost]

Last week, while waiting for the monorail at the Grand Floridian station, my wife pointed out to me how much the monorail track beam in the station was swaying after a monorail had just gone through the station. Similarly, when our monorail approached, the track began to shake/sway again. And this was not just a little vibration, but visible movement of several inches side to side swaying/rocking.

I figure this must be normal, though I can't find any discussion of this anywhere. Has anyone else ever noticed this?

I'm thinking it had more to do with light refraction or optical illusion. It is solid concrete, it isn't visibly moving back and forth. It does have room for expansion and contractions due to temperatures, but, if anyone could see those movements they would have to have eyesight that would be coveted by Superman.

 

[judino28]

Then perhaps my wife and I both have Superman eyesight, lol.

But, in all seriousness, it sure seemed to be moving to both of us, only when a train approached or left, and just the portion of track actually “sandwiched” in the station, for lack of a better term. It was a shake/sway/rocking motion, just in that “center” section, maybe 3-5 inches in both directions. We had never noticed it before, but there didn’t seem to be many variables to cause it to be an illusion.

 

[tractor tipper]

My best guess would be: If you were stationary at the station when the other train passed you were probably "rocked" by the air turbulence of the passing train.

 

[judino28]

My best guess would be: If you were stationary at the station when the other train passed you were probably "rocked" by the air turbulence of the passing train.

We definitely didn’t move. It was almost as if that section of the track was/is on a floating hinge or something. I know it sounds a bit crazy, and I was definitely skeptical when my wife mentioned it and I only caught the tail end of it the first time, but then I saw it happen again.

It doesn’t seem possible, as it’s solid concrete, I know, but that section of track in the Grand Floridian station sure seemed to be rocking back and forth. The best I can describe is as I did above: it was like it was on a floating hinge. And there do seem to be some sort of steel plates or something there, near to where it also says “high voltage” on the track.

 

[bingie]

Perhaps the contemporary moved and the track didn't? It is built on a swamp....

 

[POLY LOVER]

Then perhaps my wife and I both have Superman eyesight, lol.

But, in all seriousness, it sure seemed to be moving to both of us, only when a train approached or left, and just the portion of track actually “sandwiched” in the station, for lack of a better term. It was a shake/sway/rocking motion, just in that “center” section, maybe 3-5 inches in both directions. We had never noticed it before, but there didn’t seem to be many variables to cause it to be an illusion.

Did you report it?

 

[s8film40]

Last week, while waiting for the monorail at the Grand Floridian station, my wife pointed out to me how much the monorail track beam in the station was swaying after a monorail had just gone through the station. Similarly, when our monorail approached, the track began to shake/sway again. And this was not just a little vibration, but visible movement of several inches side to side swaying/rocking.

I figure this must be normal, though I can't find any discussion of this anywhere. Has anyone else ever noticed this?

Totally normal. If you happen to catch it just right which is after an express train passes (sounds like you did) it’s pretty amazing to see how much it moves. Most people never notice it.

 

[s8film40]

I'm thinking it had more to do with light refraction or optical illusion. It is solid concrete, it isn't visibly moving back and forth. It does have room for expansion and contractions due to temperatures, but, if anyone could see those movements they would have to have eyesight that would be coveted by Superman.

It’s actually hollow and yes it moves quite a bit.

 

[judino28]

Totally normal. If you happen to catch it just right which is after an express train passes (sounds like you did) it’s pretty amazing to see how much it moves. Most people never notice it.

That’s exactly what happened! Thanks for validating that we aren’t crazy! Haha

Any idea what causes the movement? Is it just the weight of the monorail? Is the beam on a floating hinge or is it the entire track and supports that move?

 

[s8film40]

That’s exactly what happened! Thanks for validating that we aren’t crazy! Haha

Any idea what causes the movement? Is it just the weight of the monorail? Is the beam on a floating hinge or is it the entire track and supports that move?

It’s just the sway from the vibration of the train moving on the beam. The beams are flexible it’s how they are designed to take the force of the trains moving on them. You see it more in the center of the beam sections. It’s similar to if you’re in a parking garage or on a bridge and when cars drive by you feel that little bit of bounce.

 

[Goofyernmost]

It’s actually hollow and yes it moves quite a bit.

I'm not saying your wrong, I wasn't there when it was built, but, those beams have to be pre-stressed and I don't know how they would do that with a hollow beam. Could be something I haven't heard of before... I'm old enough to know that I don't have a handle on everything. The movement would have to be from the center of the beam and not where it sits on the support. Up and down I could understand, but, there being enough to be noticeable to the naked eye is nothing short of a miracle and another reason why I never feel comfortable while riding the Monorail out of the MK side of the Contemporary.

 

[s8film40]

I'm not saying your wrong, I wasn't there when it was built, but, those beams have to be pre-stressed and I don't know how they would do that with a hollow beam. Could be something I haven't heard of before... I'm old enough to know that I don't have a handle on everything. The movement would have to be from the center of the beam and not where it sits on the support. Up and down I could understand, but, there being enough to be noticeable to the naked eye is nothing short of a miracle and another reason why I never feel comfortable while riding the Monorail out of the MK side of the Contemporary.

Here's the technical info on the beams.
http://www.concretetech.com/concrete-projects/mass-transit---walt-disney-world-monorail
I always heard something about them using styrofoam to create the hollow portion, not sure if I believe it or if its true but seems plausible I guess. As far as the movement it's very subtle, but can be a little unsettling to many because they view the beams as hard and solid. It's noticeable mostly because in the station you have a point of reference since you can see the beam directly next to the station platform. If you're in a stopped monorail when another train passes you can also feel these movements, most people really don't ever seem to think much of that but it's the same thing.

 

[Driver]

Here's the technical info on the beams.
http://www.concretetech.com/concrete-projects/mass-transit---walt-disney-world-monorail
I always heard something about them using styrofoam to create the hollow portion, not sure if I believe it or if its true but seems plausible I guess. As far as the movement it's very subtle, but can be a little unsettling to many because they view the beams as hard and solid. It's noticeable mostly because in the station you have a point of reference since you can see the beam directly next to the station platform. If you're in a stopped monorail when another train passes you can also feel these movements, most people really don't ever seem to think much of that but it's the same thing.

The beam does have a hollow section approximately 6" in diameter. I worked construction 35 yrs. buildings and bridges etc. have to flex otherwise they would crumble. Another example of unnerving movement that you can experience is on the pedestrian bridge that crosses over BVD from Team Disney to the Springs. Get on it with about 100 people or so and it starts to oscillate up and down. It's not going anywhere it's just the way it is. Regular bridges do this especially when big trucks are on them. I have worked on them in the past directly under the roadway and when the big rigs go over if you where up close enough it would oscillate up and down and tap you on the hard hat.

 

[lazyboy97o]

I'm not saying your wrong, I wasn't there when it was built, but, those beams have to be pre-stressed and I don't know how they would do that with a hollow beam. Could be something I haven't heard of before... I'm old enough to know that I don't have a handle on everything. The movement would have to be from the center of the beam and not where it sits on the support. Up and down I could understand, but, there being enough to be noticeable to the naked eye is nothing short of a miracle and another reason why I never feel comfortable while riding the Monorail out of the MK side of the Contemporary.

Simply supported prestressed concrete beams are susceptible to rolling. The monorail beams don’t have any lateral support to deal with those forces so they are able to move instead of buckle. It isn’t a miracle.

 

[POLY LOVER]

I once saw space ship earth move after a few drinks in Mexico.

 

[Skibum1970]

Want to see something interesting and scary? Look up on Youtube the Rattler coaster swaying. This was before they converted it to RMC.

 

[Dead2009]

I once saw space ship earth move after a few drinks in Mexico.

I believe it