By Papri Sri Raman, IANS
Rameswaram (Tamil Nadu) : Memories of migrations and times gone by stare out of every span of this British-built bridge. It is set to open to train traffic again, this time in broad gauge tracks, linking mainland Tamil Nadu with the Hindu holy town of Rameswaram.
The Pamban Bridge connects Mandapam at the edge of south India to Pamban Island on the Bay of Bengal where Rameswaram thrives. Until 1911 people crossed by boat to visit an ancient Ram temple at Rameswaram, 600 km south of Chennai.
The British built the bridge in 1913-14 across the Palk Strait dividing India and Sri Lanka for a regular train service when they decided to hire workers from Tamil Nadu to tea plantations in the island nation.
It was a time when the Tamil people of Serendip (now Sri Lanka) and the subcontinent saw themselves as one. The Boat Mail chugged on the narrow track, going right up to Land’s End, 27 km south of Rameswaram.
At Dhanushkodi, the Indo-Ceylon Express and the Rameswaram Express disgorged thousands, and they took a 20-km Irvin and Goschen steamer ride to and from the emerald island for work and marriages.
A railhead at Thalaimannar, on the Sri Lankan side, took the labourers to the highland estates.
The rail track also brought to Rameswaram trains full of pilgrims from Gujarat, Uttar Pradesh and Bihar – almost entire villages travelling together to make that once-in-a-lifetime trip to the Ram temple at the very place from where the Hindu god is said to have launched his battle against Ravana. They still come in packed trains every year.
A cyclone in 1964 washed away the track from Rameswaram to Dhanushkodi as well as a train full of people. Several grids of the Pamban Bridge were broken.
The bridge is a bridge-building example in many ways.
It came up at a time when engineers across the world were suddenly faced with technology failures. The two most memorable collapses were the Tay Bridge collapse in Britain and the Ashtabula Bridge collapse in Ohio in 1876 – around 80 people lost their lives in each of the accidents.
Exceptionally strong vibrations due to wind stresses under a moving load created instability, and eventual collapse of the Tay Bridge. It took engineers 25-30 years to find that forces could be broken into vertical and horizontal components, and joints could be used to diffuse stress on spans.
The bridge in Tamil Nadu was built according to specifications patented by German engineer William Scherzer and there is a plea to make it an UNESCO World Heritage site.
Built with just Rs.2 million in two years by 600 workers, it is 2.06-km long, running over 10-feet deep water at places. Just strengthening it structurally this year has cost nearly Rs.250 million.
It sits on an artificial sandstone reef. Nearly 5,000 tonnes of cement, 18,000 cubic feet of crushed metal stone, 2,600 tonnes of steel and 80,000 cubic feet of boulders were used to build it.
The bridge has 145 fixed spans, and one-navigation span (a total of 225 feet) that opens for ships. The drawbridge at the centre comprises two sections of the navigation span, called the Scherzer span. Each weighs 415 tonnes.
It is a spectacular sight when drawn up to let ships through.
It requires six people on each side to manually operate and lift the moving sections for ships to pass. Experts from Indian Institute of Technology, Madras, are now engaged in motorising the moveable span.
After the 1964 cyclone, the girders of Pamban bridge were replaced and an anemometer was installed. When the wind speed crosses 55 km per hour, signals on the bridge send out an automatic warning to approaching trains.
The Pamban bridge has been closed since June 2006, to change the meter gauge rail track to broad gauge.
“We used 450 workers. People had to work at a height of 50 feet above sea level in 55 km per hour wind speeds,” Divisional Manager Hemant Kumar told IANS.
After the gauge conversion, the first ship was allowed to pass under the bridge June 21. The bridge, which is ready for broad gauge traffic, will be inaugurated in a few days time.