General Information
Figure 1 shows a pedestrian suspension bridge.
| Type | Single-span suspension bridge |
| Main span | ≅ 10 m |
| Deck width | ≅ 0.6 m |
| Pylon | Timber logs (shore 1); timber log and trees (shore 2) |
| Girder | Bamboo transverse beam |
Vibration
Figure 2 shows the pylon on shore 1.
The pylon is made of timber logs and consists of two verticals (1 and 2), three cross-beams (3 to 5), and a brace, which consists of a vertical (6) and a diagonal (7). Vertical 1 is connected to diagonal 7 by nails. The verticals' bases are embedded in the ground, the cross-beams are connected by nails, and diagonal 7 is tied to vertical 6 by a rope and a short bamboo pole. The main cables are made of ropes; they pass over cross-beams 4 and 5 and are tied to cross-beam 3. The pylon height h ≅ 2 m, and the width b ≅ 0.7 m. Figure 3 shows the opposite pylon.
The pylon is made of two trees (1 and 2) and a timber log. The former are the verticals, while the latter is the cross-beam, which is tied to the verticals by ropes and short bamboo poles. Tree 1 is smaller and differently shaped than tree 2, and the main cables are tied to the cross-beam. The height h1 and the width b1 ≅ 2 m. Figure 4 shows a main span sector.
The deck consists of six bamboo poles placed side-by-side that are tied together by ropes. The hanger cables (also made of ropes) are tied to the main cables, the girders, and the deck's external poles. Figure 5 shows a front view of the pylon on shore 1.
Abutment are not installed; the bamboo poles' ends are placed directly over the creek banks. There is an eccentricity (e) between the axes of the deck and the pylon, which affects the angles of the main- and hanger cables. Figure 6 shows a schematic layout of the bridge.
The vertical vibration of the main span during pedestrian-induced excitation is shown in video 1.
Video 2 shows the pylon vibration on shore 1 during pedestrian-induced excitation.