Polymorf - Knowhere - Cable stayed bridge




(static demonstration model)		(scale visualization model)
		click image to enlarge

Fig. 189 - The parabolic curve of the suspension cables mirrors bending moment diagram

The main suspension cables are spun together from thousands of strands of high strength

steel wire. At the top of the towers these cables pass over a saddle that allows the cable to

slide as the loads pull from either side of the tower. Here is where the tensile stresses of

the cables are transferred to the towers which displace them downward as compression

stresses to the ground.

As shown in Fig. 189 above, suspension bridges carry their loads very efficiently due to the

fact that the parabolic curve if the main cables closely conforms to the force of the bending

moment experienced by the bridge along the length of its deck. Recall that the bending

moment of a simply supported beam is zero at the end supports and then increases to a

maximum in the middle of the beam. The same is true for a suspension bridge.

Cable stayed bridge

Cable stayed bridges are similar to suspension bridges in most respects except for the way

that the deck is hung from the support towers. Instead of long suspension cables that

extend from one end of the bridge to the other, numerous individual cables extend directly

from each tower to the deck.


	(static demonstration model)
.		(scale visualization model)
Fig. 190 - Cable stayed bridge click image to enlarge

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