Pamban Bridge
More than a century ago, in 1911, started the construction of India’s first sea bridge – the Pamban Bridge which connects the town of Mandapam in mainland India with Pamban Island and Rameswaram. A cantilever steel bridge supported by concrete piers, was completed within 3 years despite the minimum availability of technologies back in those days and was the longest sea bridge in India until the opening of the Bandra-Worli Sea Link in 2010.
The Pamban Bridge also called as Cantilever Scherzer Rolling Lift Bridge; was named after the German engineer Scherzer, who built the Pamban viaduct; has a road bridge that was constructed parallel to the original rail bridge back in 1988 which connects National Highway 49 with the island of Rameshwaram. It is built over the majestic Bay of Bengal; to be precise, it is built over the Palk Strait. The construction was also a very challenging one for it being built on the second most corrosive environment in the world, after Florida, due to frequent cyclones.
The unique feature of the bridge is a span right in the middle that can lift up to let the ships pass underneath it. These movements are subject to traffic protocol between the railway and the maritime authorities.
Planning And Structural Aspects
In 1870, the British Administration suggested plans for a bridge to connect to the mainland to increase trade with Ceylon, Sri Lanka. The construction began in the August of 1911 and was opened for the public on the 24th of February, 1914. The adjacent road bridge was opened in 1988. The railway bridge is located 12.5 m (41 ft) above sea level and consists of 143 piers and has a double-leaf bascule section with a Scherzer rolling type lift span that can be raised to let ships pass. Each half of the lifting span weighs 415 tonnes (457 tons). The two leaves of the bridge are opened manually using levers.
It spectacularly opens up to allow ships and vessels to pass through where 10-15 boats and small ships pass beneath the bridge every month. The Scherzer roll and lift span are activated by using the principle of spurs and gears to gain a large amount of mechanical advantage. Since it is operated manually, the bridge is lifted for the passage of the vessels. The Port-Officer informs the bridge operator the date and time of crossing of the transport. The bridge operator informs the Station Master and the Controller before he lifts the bridge. The entire operation takes nearly 40 to 50 minutes.
In 1964, the bridge survived a cyclone that flattened the port town of Dhanushkodi. The bridge survived and was reinforced within 46 days, by E. Sreedharan, the man behind the construction of the Delhi Metro.
Considered by the National geographic channel as the second deadliest railway line in the world, the bridge is prone to high corrosion and cyclones, maintenance is a tedious job.
Materials Used
The stone and concrete metals used for the bridge were brought by rail from a quarry which was situated 270 km away from Pamban. Sand came from a site 100 km away. 4,000 tons of cement, 1,36,000 cubic feet of clay, 18000 cubic feet of crushed metal, 163000 cubic feet of sand and 80,000 cubic feet of boulders were used to construct the Pamban Railway Bridge.
The stone and concrete metals used for the bridge were brought by rail from a quarry which was situated 270 km away from Pamban. Sand came from a site 100 km away. 4,000 tons of cement, 1,36,000 cubic feet of clay, 18000 cubic feet of crushed metal, 163000 cubic feet of sand and 80,000 cubic feet of boulders were used to construct the Pamban Railway Bridge.
The Old Pamban Bridge has played a crucial role in connecting Pamban Island with mainland India. Thge coming months would witness the old Pamban Bridge to be
replaced with the new Pamban Bridge, for which an estimated amount of `280 crore has being invested. All set to become the nation’s first Vertical Lift Railway Sea Bridge, this new dual track bridge which would be 2.07 km long, is planned to be constructed in automotive mode, the help of modern technologies, allowing two ships to pass this bridge at the same time. The bridge is scheduled to be completed by the month of March next year.
Interesting Facts -
Withstood Cyclone
In 1964, a massive cyclonic storm which had flattened Dhanushkodi - a nearby (now abandoned) town, hugely damaged the Pamban Bridge with many of its parts being washed away, the rolling life centre span withstood any damages.
The Bridge Almost Shut Down
In 2006, owing to the start of Project Unigauge, it was decided that the bridge would have to be shut down as it has metro gauge rails. There were plans proposed for the new bridge under a huge budget. Under the supervision of A.P.J. Abdul Kalam, who was the President then and was from Rameswaram too, the bridge was renovated and resumed services in 2007.
Remarkable Strength
The Pamban Bridge is located at an area of immense corrosive potential, second only to the Gulf of Mexico in the world. Even so, it has stayed strong throughout the years, with over a century of continuous service. In 2013, a 220 ton barge crashed into the bridge when its tugboat ran aground, causing the piers to tilt. Damages were only minor and it was soon repaired.
Reference
1. https://readcivil.com/how-pamban-bridge-was-constructed/
2. https://civildigital.com/pamban-bridge-the-crown-of-south-indian-railway/
3. https://www.financialexpress.com/infrastructure/railways/indianrailways-1st-vertical-lift-sea-bridge-at-rameswaram-new-pamban-bridge-to-be-ready-soon/2344039/
4. https://www.nativeplanet.com/travel-guide/interesting-facts-about-pamban-bridge-rameswaram-002462.html
By -
Tuhina Chatterjee, Associate Editor, Civil Engineering and Construction Review
