Rama IX Bridge


Rama IX Bridge is a bridge in Bangkok, Thailand over the Chao Phraya River. It connects the Yan Nawa District to Rat Burana District as a part of the Dao Khanong – Port Section of Chalerm Maha Nakhon Expressway.
The bridge was named in the honor of King Bhumibol Adulyadej's 60th birthday. The opening date coincides with the king's birthday. It was the first cable-stayed bridge in Thailand and had the second-longest cable-stayed span in the world when it opened in 1987.
The original colour scheme, with white pylons and black cables, was replaced with an all yellow scheme representing the king in 2006.

Bridge structure

The steel superstructure includes the bridge, rigged mast, and cable. The main span of the bridge, which is stretched between two poles, has a length of 450 meters. The main span is a trapezoid 33 meters wide. The bridge has a walkway along its side. The bridge has two main pylons 3 x 4.50 meters. This serves to hold the tension of the cable and weight into the pylon pier. The 121 – 167 mm diameter cables consist of many small wires wound together. The cables vary in length from 50 to 223 meters can absorb the tension for 1,500–3,000 tons.