Bridge Building 2016

[FrankHerman]

Hi my name is Frank Herman and I am competing in Science Olympiad Bridge building. I am having a hard time building bridges. If you guys have any useful tips or tricks, and or bridge designs, It would be much appreciated if you would share them.

Thanks,
Frank

[DoctaDave]

Hi my name is Frank Herman and I am competing in Science Olympiad Bridge building. I am having a hard time building bridges. If you guys have any useful tips or tricks, and or bridge designs, It would be much appreciated if you would share them.

Thanks,
Frank

Read through the entire Bridge building forum this year and last year, which seems like a daunting task, but you can probably tell which posts to thoroughly read and which ones to skip over. There is a lot of good information in those posts right at your fingertips. The wiki page on this site is also a good place to start if you are just beginning. It's hard to give you tips if you don't have a specific problem.

Good luck and have fun!

[Unome]

Hi my name is Frank Herman and I am competing in Science Olympiad Bridge building. I am having a hard time building bridges. If you guys have any useful tips or tricks, and or bridge designs, It would be much appreciated if you would share them.

Thanks,
Frank

Threads from previous years about this event rotation (Boomilever, Towers or Tower Building, & Elevated Bridge) are also helpful, especially in more general matters like gluing effectively.

[nxtscholar]

So someone correct me if I'm wrong (I'm a biomathematics major, although one with a strong interest in engineering), but I had a sudden pop into my mind that I'm rather curious about.

Does this year's rules with regards to the test support actually affect division B more and thus pose a bigger challenge to them than division C? Like, by nature of the rules, division C bridges are longer than division B bridges because of a longer mandated span. Consequently, the test support creates a larger angle of inclination for division B bridges than division C bridges. I'm going along the lines of simple geometry. For division C, it's a "rise" of 5 cm to a "run" of 45 cm. For division B, it's about a rise of 5 cm to run of 35 cm.

Thus, doesn't this create a larger change in the direction of forces and stress for division B than division C compared to last year? In other words, don't division B teams have more to change in their designs than division C with regards to changing truss designs, thickness of members, etc.?

I emphasize, however, that regardless of division, the test support doesn't seem to be changing the problem that much. But the question I ask is does division B technically have more to deal with than division C in terms of change?

[bernard]

So someone correct me if I'm wrong (I'm a biomathematics major, although one with a strong interest in engineering), but I had a sudden pop into my mind that I'm rather curious about.

Does this year's rules with regards to the test support actually affect division B more and thus pose a bigger challenge to them than division C? Like, by nature of the rules, division C bridges are longer than division B bridges because of a longer mandated span. Consequently, the test support creates a larger angle of inclination for division B bridges than division C bridges. I'm going along the lines of simple geometry. For division C, it's a "rise" of 5 cm to a "run" of 45 cm. For division B, it's about a rise of 5 cm to run of 35 cm.

Thus, doesn't this create a larger change in the direction of forces and stress for division B than division C compared to last year? In other words, don't division B teams have more to change in their designs than division C with regards to changing truss designs, thickness of members, etc.?

I emphasize, however, that regardless of division, the test support doesn't seem to be changing the problem that much. But the question I ask is does division B technically have more to deal with than division C in terms of change?

I don't have an answer at this hour but the different spans brings up another question: does the "tilt" have more of an effect for a large angle change involving a short span or a smaller angle involving a longer span? Does span or angle affect the challenge more? I would guess the span's added challenge dramatically increases with greater spans, with greater angles adding more challenge but with less of a magnitude. Just a guess coming from a sleepy person though.

[nxtscholar]

So someone correct me if I'm wrong (I'm a biomathematics major, although one with a strong interest in engineering), but I had a sudden pop into my mind that I'm rather curious about.

Does this year's rules with regards to the test support actually affect division B more and thus pose a bigger challenge to them than division C? Like, by nature of the rules, division C bridges are longer than division B bridges because of a longer mandated span. Consequently, the test support creates a larger angle of inclination for division B bridges than division C bridges. I'm going along the lines of simple geometry. For division C, it's a "rise" of 5 cm to a "run" of 45 cm. For division B, it's about a rise of 5 cm to run of 35 cm.

Thus, doesn't this create a larger change in the direction of forces and stress for division B than division C compared to last year? In other words, don't division B teams have more to change in their designs than division C with regards to changing truss designs, thickness of members, etc.?

I emphasize, however, that regardless of division, the test support doesn't seem to be changing the problem that much. But the question I ask is does division B technically have more to deal with than division C in terms of change?

I don't have an answer at this hour but the different spans brings up another question: does the "tilt" have more of an effect for a large angle change involving a short span or a smaller angle involving a longer span? Does span or angle affect the challenge more? I would guess the span's added challenge dramatically increases with greater spans, with greater angles adding more challenge but with less of a magnitude. Just a guess coming from a sleepy person though.

Oh that is true...it's possible a change in angle impacts longer span bridges faster than shorter span bridges. But I don't take statics, so...

[bernard]

So someone correct me if I'm wrong (I'm a biomathematics major, although one with a strong interest in engineering), but I had a sudden pop into my mind that I'm rather curious about.

Does this year's rules with regards to the test support actually affect division B more and thus pose a bigger challenge to them than division C? Like, by nature of the rules, division C bridges are longer than division B bridges because of a longer mandated span. Consequently, the test support creates a larger angle of inclination for division B bridges than division C bridges. I'm going along the lines of simple geometry. For division C, it's a "rise" of 5 cm to a "run" of 45 cm. For division B, it's about a rise of 5 cm to run of 35 cm.

Thus, doesn't this create a larger change in the direction of forces and stress for division B than division C compared to last year? In other words, don't division B teams have more to change in their designs than division C with regards to changing truss designs, thickness of members, etc.?

I emphasize, however, that regardless of division, the test support doesn't seem to be changing the problem that much. But the question I ask is does division B technically have more to deal with than division C in terms of change?

I don't have an answer at this hour but the different spans brings up another question: does the "tilt" have more of an effect for a large angle change involving a short span or a smaller angle involving a longer span? Does span or angle affect the challenge more? I would guess the span's added challenge dramatically increases with greater spans, with greater angles adding more challenge but with less of a magnitude. Just a guess coming from a sleepy person though.

Oh that is true...it's possible a change in angle impacts longer span bridges faster than shorter span bridges. But I don't take statics, so... :P

With the chair setup at the NJIT regional, I think you'd also need some experience with dynamics...

[dholdgreve]

So someone correct me if I'm wrong (I'm a biomathematics major, although one with a strong interest in engineering), but I had a sudden pop into my mind that I'm rather curious about.

Does this year's rules with regards to the test support actually affect division B more and thus pose a bigger challenge to them than division C? Like, by nature of the rules, division C bridges are longer than division B bridges because of a longer mandated span. Consequently, the test support creates a larger angle of inclination for division B bridges than division C bridges. I'm going along the lines of simple geometry. For division C, it's a "rise" of 5 cm to a "run" of 45 cm. For division B, it's about a rise of 5 cm to run of 35 cm.

Thus, doesn't this create a larger change in the direction of forces and stress for division B than division C compared to last year? In other words, don't division B teams have more to change in their designs than division C with regards to changing truss designs, thickness of members, etc.?

I emphasize, however, that regardless of division, the test support doesn't seem to be changing the problem that much. But the question I ask is does division B technically have more to deal with than division C in terms of change?

I see where you are coming from, and yes, as the span decreases, the angle of the bridge increases... depending on how you design your bridge... In theory, you could design an elevated bridge, then chop off the elevated legs on one side... In that case, there is no angle due to the elevation change.

[Phys1cs]

I see where you are coming from, and yes, as the span decreases, the angle of the bridge increases... depending on how you design your bridge... In theory, you could design an elevated bridge, then chop off the elevated legs on one side... In that case, there is no angle due to the elevation change.

The issue with just building an elevated bridge and chopping off one sides legs is the maximum 2cm clearance on the not inclined side. You couldn't build 5cm high legs, since that would be higher than the allowed height of the lower side. You could possibly build 1.5-2cm high legs, but I don't think that would be the most efficient solution to the problem. Though it does make the angle a little smaller

[dholdgreve]

So someone correct me if I'm wrong (I'm a biomathematics major, although one with a strong interest in engineering), but I had a sudden pop into my mind that I'm rather curious about.

Does this year's rules with regards to the test support actually affect division B more and thus pose a bigger challenge to them than division C? Like, by nature of the rules, division C bridges are longer than division B bridges because of a longer mandated span. Consequently, the test support creates a larger angle of inclination for division B bridges than division C bridges. I'm going along the lines of simple geometry. For division C, it's a "rise" of 5 cm to a "run" of 45 cm. For division B, it's about a rise of 5 cm to run of 35 cm.

Thus, doesn't this create a larger change in the direction of forces and stress for division B than division C compared to last year? In other words, don't division B teams have more to change in their designs than division C with regards to changing truss designs, thickness of members, etc.?

I emphasize, however, that regardless of division, the test support doesn't seem to be changing the problem that much. But the question I ask is does division B technically have more to deal with than division C in terms of change?

I see where you are coming from, and yes, as the span decreases, the angle of the bridge increases... depending on how you design your bridge... In theory, you could design an elevated bridge, then chop off the elevated legs on one side... In that case, there is no angle due to the elevation change.

You can if you slope the leg inward, so at the point where the opening starts it is equal to or less than 2 CM