Suspension bridges are among the oldest of all bridge designs. Their main supporting element is a flexible cable. Since cables are able to absorb high tensile forces while themselves having little dead-weight, they enable wide-span suspension bridges to be constructed. This makes it possible to bridge longer distances with no supporting pillars, such as over wide gorges. The sag of suspension bridge supporting cables is parabolic in shape, as the weights are attached at relatively short, constant intervals by way of vertical cables to the main supporting cables.
The experimental setup SE 110.18 represents a suspension bridge. The bridge consists of two parallel supporting cables with a roadway suspended between them. U-shaped hangers serve as vertical cables. They are attached to the main supporting cables at regular intervals, and hold the roadway. Deflection rollers act as pylons. The roadway acts upon the supporting cables as a distributed load, and can be loaded by additional weights.
Two roadways with different stiffness are available: one stiff and one elastic roadway. The stiff roadway has a hinge in the middle. The hinge permits internal moments in the roadway occurring in response to uneven loading to be visualised – the roadway buckles.
The experimental setup without roadway deals with free-hanging cables. Cables with different dead-weights are studied by attaching additional point loads directly to the supporting cables.
The tensile forces in the supporting cables are determined with the aid of weights. The maximum sag is measured using a scaled rule. The scaled rule is fixed to a cross-arm.
All the component elements of the experiment are clearly laid-out and housed securely in a storage system. The complete experimental setup is arranged in the frame SE 112.