Located in the port city of Chennai, near the Covum river estuary, this project is part of a 20 KM elevated viaduct which is meant to carry container traffic from Chennai port, directly outside the city limits, so that port traffic does not interfere with daily city traffic. Additionally, the viaduct is also a double decker structure, with the 2nd level meant for uninterupted port traffic, and the first level meant for city traffic. Thus, first level also has a number of up and down ramps along the length of the viaduct.
Both the first level and 2nd level are single cell strutted box with segmental construction methodology. Twin level piers are provided with bored cast in situ piles. Additionally, the alignment follows the flow of covum river with almost the entire alignement in curvatures of various radii, making many of the spans unique and varied.
A special span near the river estuary is provided with Extradosed bridge of span 75m+150m+75m to carry the traffic over the widest point of the river. As the alignment travels over many existing bridges, 10 obligatory spans of 50m are also provided which are to be constructed over existing running bridges.
With a total of 260 spans and equal number of foundation, most of which are unique due to varying curvatures and significant geometry constraints, the most challenging part of the project lies in the construction friendliness of the design and to enable construction for the entire stretch in 30 months.
