G-Force versus Support Types.

Do support types (straight or slanted) have anything to do with g-force intensity? I'm not sure how they work technically.

[Coasterkidmwm]

If you need more support because it's in a high G area or the span of track between supports is greater, thicker supports help. In the linked image I've attached, the support in the background is under a heavier G load than the support in the foreground (and the diagonal bean you see in the uh.... fore-est foreground), which is in a floaty section. They have roughly the same span of track between them and are nearly the same height but not quite. Also the single pole with the stairs around it is for the block brake (remember it's by itself, it's not an A shape and has no diagonal beams coming out of it), where not much in the way of G's is happening and you can compare its thickness as well.

I'm not an engineer though they'll know better. This has to be loaded with situation-related exceptions (earthquakes, supports dodging something, etc). Hope this helps.

[mkingy]

Simple answer is yes they do.

CK is correct - support density and thickness contribute to the size of support.

The straight support is there to deal with straight up vertical forces such as the weight of the track and any force acting straight down (for instance in the valley of a straight drop).

Angled supports could be there for a multitude of reasons. In the case of the picture CK posted they provide support against the forces created in the support by the banking. It acts in compression to stop the vertical support bending. On the other hand a large A-frame would be there to spread the vertical load between two supports AND provide lateral support.

[Coasterkidmwm]

Out of curiosity does steel respond better to being under the same load of compression or tension?

[mkingy]

Tension (I've been trying to work out if that lateral will be in tension or compression but my brain is fried after a day of work - I've edited that post about 3 times now) - in compression the steel would buckle rather than squash.

If people are interested I could maybe write something on the principles behind this stuff.

[gouldy]

Steel loves tension. Steel is all over it when it comes to tension. That's pretty much of the basis of suspension bridges, of course. Steel is still good at dealing with compression, just not as good as it is at dealing with tension.

What's not great at dealing with tension, though, is where the support is bolted to the floor - that component is FAR better at dealing with compression than tension. You'll tend to see support structure is set in the direction of compression wherever possible, because I would imagine that slightly more supports may be required for support structure under tension, purely because of the extra required anchor points with the floor or other nearby structures.

[Coasterkidmwm]

Good to know! I always wondered why more companies didn't align supports on the "inside" of a turn to save space when they're not required to, and when they do it's always in the center of a helix (because it can be a giant anchor point). Thank you.

Yeah the footers and foundation of the coaster is still concrete. Reinforced concrete but it's still bad with the tension forces. My guess would be that it the building method used in the reinforced structure might differ drastically with the designs where you can see there should be a lot of tension.

The concrete handles compression very well and the rebar handles the tension. If a footer was going to be in a lot of tension, my guess is they will add more rebar. I will learn for sure when I take my concrete class next year.

I need to bump this thread again, because I want to know whether or not... you look at actual coaster support photos when building your own tracks.

[Dirk_Ermen]

lol240 wrote:

I need to bump this thread again, because I want to know whether or not... you look at actual coaster support photos when building your own tracks.

Myself I work on my own gut feelings. If it looks under or oversupported, I'm changing it.

[mkingy]

lol240 wrote:

I need to bump this thread again, because I want to know whether or not... you look at actual coaster support photos when building your own tracks.

Naturally we do - for instance Dirk's gut feeling (or experience-based knowledge) will come from seeing thousands upon thousands of rollercoaster supports and comparing them to what he sees on a design!