Corroding Howrah bridge to get a Fiber glass makeover

June 6, 2012

Howrah Bridge- The busiest cantilever bridge in the world connecting the twin cities of Kolkata and Howrah, set to undergo a major makeover and maintenance. The Kolkata Port trust (KoPT) — which is in charge of the bridge, is likely to spend more than Rs 20 lakh for this maintenance. KoPT is inviting bids for installing fibre glass casing on the 74 columns of the bridge hanger base to protect it from human spitting. A similar effort was made in 2004 also when KoPT spend about Rs 65 lakh to repaint the bridge with two coats of aluminium paint, to combat corrosion happened due to bird droppings.

For the mean time, the authorities have started painting primer Zinc Chromate which is in Yellow color as a temporary measure.

Why the Bridge needs a make-over?

The bridge requires a makeover as it faces threat of corrosion.
Major factors of the corrosion are: Urinating, Human Spitting and Bird Droppings. To a minor extent, salt content in air also.
As per a recent report, spitting had reduced the thickness of steel hoods covering the pillars from 6 mm to less than 3 mm since 2007.

Highlights of Howrah Bridge:

The Howrah Bridge is a cantilever bridge that spans the Hooghly River in West Bengal, India.
Commissioned: 1943.
Oiginally named: New Howrah Bridge
On 14 June 1965 it was renames as “Rabindra Setu”, after Rabindranath Tagore
Yet popularly known as the “Howrah Bridge”.
Make: High-tensile alloy of steel Tiscrom.
Tata Steel was the supplier of the steel.
The busiest cantilever bridge in the world
Currently the sixth longest cantilever bridge in the world.

What is a Cantilever Bridge?

A cantilever bridge is a bridge built using cantilevers, structures that project horizontally into space, supported on only one end.