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3x3 Table |
| Bascule Bridge | Suspension Bridge | Truss Bridge |
| Pros
A bascule Bride is a good protection of traffic because the leaf of the deck
trunnion bascule forms a traffic barrier.
Bascule Bridges
must resist wind loading to a greater extent than other common movable
bridges types.
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Pros The center span may be made very long in proportion to the amount of materials required, allowing the bridge to economically span a very wide canyon or waterway. It can be built high over water to allow the passage of very tall ships. Neither temporary central supports nor access from beneath is required for construction, allowing it to span a deep rift or busy or turbulent waterway. Being relatively flexible it can flex under severe wind and seismic conditions, where a more rigid bridge would have to be made much stronger and so also heavier. Lacking stiffness the bridge may become unusable in turbulent and strong wind conditions and so require temporary closure to traffic.
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Pros
When building out of a material that can take both tension (stretching) and
compression (squeezing), the truss bridge is fairly economical in the amount
of material it uses.
Truss bridges are more rigid than most other bridge types this is usually an advantage as it can help avoid problems with oscillation. Truss bridges are usually built mostly on-site. Beam bridges often have the beams (and sometimes the deck) made at a factory and trucked to the site of the bridge. Building at a factory is usually cheaper than building on site. center span may be made very long in proportion to the amount of materials |
| Cons Severe wind loading occurs only with the bridge in the open position; thus, it is not combined with live load and can be sustained at higher allowable stresses. Wind loading requires the bascule bridge machinery to be much more robust than it otherwise would have to be and is a bigger part of the machinery design for bascule bridge than for vertical lift or swing bridges.
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Cons Lacking stiffness the bridge may become unusable in turbulent and strong wind conditions and so require temporary closure to traffic. Being flexible in response to concentrated loads the structure is generally not used for regional rail crossings, which concentrate the maximum "live" loading at the location of the locomotives. Under severe wind loading, the towers exert a large torque force in the ground, and thus require very expensive foundation work when building on soft ground.
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Cons Steel truss bridges may require repeated painting to keep them from rusting. With a reinforced concrete beam type bridge, painting is not usually necessary
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| Solution Bascule bridges may be single or double leaf. Double leaf bridges usually have any truss structure and counterweights below the deck, while a single leaf bridge is typically a truss bridge with an elevated counterweight.
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Solution N/A
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Solution
A combination of a bascule bridge
and a truss bridge will be adequate. The road base can be lifted by gears.
Two gears will rotate pulling the wire ropes & lifting the road bed upward
to a steel tower. Wire rope consisting of several stand twisted together
like a helix will hold the road bed on place. Straight and triangular truss
members will be bolted together to support the road bed and the bridge
itself.
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