General Information

Figure 1 shows a suspension bridge that is used by motorcycles, bicycles and pedestrians.

Sag to Main Span Ratio

Figure 2 shows a side view of the main span.

The sag s ≅ 10 m, and the main span m ≅ 250 m; that gives a sag to main span ratio of 1/25. Figure 3 shows a schematic cross-section of the bridge.

The cross-section consists mainly of a transverse girder, four stringers, and the deck. The girder consists of two side-by-side placed U-sections, while the stringers and deck are made of lipped channels. The hanger cables are connected to the girder by hooked bars, plates, and nuts. Plan bracing is not installed. Figure 4 shows a pylon.

The pylon has a height over the deck of h ≅ 10 m, which is the same height as the sag. Consequently, the main cables and the deck are about at the same elevation level in the mid-span region, as shown in figure 5.

The main cables and hooked bars are directly connected; the hanger cables are wrapped around them and fixed by U-bolt clamps. Figure 6 shows two schematic lateral views.

Bridge A is the above shown bridge; the sag to main span ratio is 1:25, and the pylon height over the deck is about 10 m. Bridge B has a sag to main span ratio of 1:10, and the pylon height over the deck is 26 m (25 m + 1 m hanger cable length in the mid-span region). The remaining bridge layout (e.g., main span, hanger cable spacing, back main cable inclination, etc.) and materials are equal on both bridges.