General Information

Figure 1 shows a pedestrian suspension bridge.

Pedestrian suspension bridge.
 Pedestrian suspension bridge in a park
Type Three-span suspension bridge
Main span ≅ 65 m
Deck width ≅ 2 m
Deck width to main span ratio ≅ 1:33
Pylon Reinforced concrete (A-type, longitudinal)
Girder Steel truss

Side Spans

Figure 2 shows a side span.

Side span.
Side span of a pedestrian suspension bridge

The side span s ≅ 18 m. Figure 3 shows the truss girder.

Truss girder.
Side span truss girder of a pedestrian suspension bridge

The truss girder is non-continuous, made of L-sections, and has a height (h) ≅ 0.9 m. Figure 4 shows two schematic lateral views.

Lateral views.
Lateral view of a three-span and a single-span suspension bridge.

Bridge A is the above shown bridge, while bridge B is bridge A with hanger-less side spans (with two approach spans).

  • Does the main span of bridge A structurally behave like the main span of bridge B?
    What are some possible reasons for choosing approach spans instead of side spans?
  • Side Span Hangers' Vibrations

    Figure 5 shows a side span.

    Side span.
    Side span of a pedestrian suspension bridge

    Video 1 shows hangers 3 and 4 during hand-induced vibration.

    Video 1. Hangers 3 and 4 during hand-induced vibration.
  • How much load is transferred from the girder to the main cable by hangers 3 and 4?