why is a bridge parabolic?

Question

i have a mini project for my pre calculus. class and i am to find an example of a parabola. now i chose a bridge and im supposed to explain how is th bridge parabolic. the problem is i don't know why it is i just know it is... can someone please help me ?

Answer 1

There are two curves with very similar shapes that are important in bridge construction. One is called a catenary and the other a parabola. At first glance, the curve may be described as a catenary. A catenary is a curve created by gravity, like holding the end of a skipping rope or a chain in each hand and letting it dangle. However, because the curve on a suspension bridge is not created by gravity alone (the forces of compression and tension are acting on it) it cannot be considered a catenary, but rather a parabola. The parabolic shape allows for the forces to be transferred to the towers, which upholds the weight of the traffic.

For the suspension bridge in general the roadway is very nearly a uniformly distributed load, and each cable hangs down in a curve closely approaching that of a parabola.

Answer 2

Do you have to explain why the bridges are parabolic or how the Bridges ar parabolic?



The parabolic shape is used for bridges because the parabola can transfer the bridge loads over the longest distances before having to use intermediate supports. Intermediate supports are expensive and sometimes impossible to construct.

The Romans used to use the arch in their construction projects for just that reason.



As far as how the bridges are parabolic you would have to come up with an equation for a parabola. Only the support structure is parabolic, the roadway is still flat.

Answer 3

The curved shape of an arched bridge shape is to imitate the 2d curve as a results of bridge loading. For an uncomplicated span bridge (one span), the 2d is best interior the midsection of the span and it is the place the bridge superstructure is the internal maximum. the 2d brought about by utilising flexure is resisted by utilising a pair between the precise and backside chord. the greater suitable this distance, the fewer the axial forces interior the chords. For non-supply up bridges, the main important 2d happens on the interior pier helps. in case you look at old metallic framed bridges of the this manner, the intensity of the superstructure is best on the piers because of the fact the 2d is best on the piers and minimum between the piers.