Early Bridges were mostly of stone or brick masonry arch. Longer spans were constructed with steel deck; this was followed by Concrete- plain, reinforced and prestressed- during the first half of the Twentieth Century. Alternate Designs by Contractors for Road Bridges facilitated fast track, economic construction of bridges between 1920 and 1980. The first ever bridge in Prestressed Concrete for the Assam Rail Link was completed in seven months (1949). The 3.2km long Sone Bridge at Dehri on Sone was designed and constructed in 33 months (1965)
The Indian Roads Congress Standard Specifications and Code of Practice for Road Bridges in India was published in 1937. Successive revisions over the years reflected improvements but at the same time introduced conservatism, increased cost and time. Construction of third and fourth Lanes of the Sone Bridge at Dehri on Sone 40 years after the original construction in 1965 took nearly double the time to complete with deeper well foundations!