The new foot-over-bridge (FOB) will be five meters wide and 75 meters in length. This new FOB will connect major platforms of Thane station, including platforms number 2&3 and 4&5 to ease the flow of passengers. The work is expected to be completed by December end of this year. The approximate cost of this stainless FOB is around Rs 4 crore.
The material to be used will be stainless steel conforming to international standards and the structure will be corrosion resistant and also reduce maintenance costs.
"The preparatory work on Central Railway’s Mumbai division's first-ever stainless steel FOB at Thane has already been started," said an officer of CR, adding that using stainless steel will make the project costlier by around 20 per cent.
However, the structure will be corrosion resistant and will reduce maintenance efforts in the corrosion-prone environment of Mumbai as compared to conventional steel, thus benefiting in the long run.
There are around 325 FOBs and road overbridges (ROBs) in the suburban railway section of Mumbai divisions of Central Railways. Corrosion in structures is one of the persistent challenges faced in coastal regions such as Mumbai and has been a contributing factor in many mishaps and unsafe structures during the past few years.
The basic difference between stainless steel and ordinary structural steel is that the former contains alloys of chromium, copper, and nickel, which enable it to resist corrosion.
Explaining the benefits of stainless steel, a senior officer of CR said, "Barring the periodic inspection and cleaning, there is hardly any maintenance cost. This means that there will be very few traffic blocks for FOB and ROB repairs."
In Mumbai, Railway authorities have to think twice before closing down a FOB because of the chaos it triggers.
"Ordinary steel structures are sensitive to atmospheric conditions. Steel corrodes readily in the presence of oxygen and moisture, but the rate of corrosion is accelerated in the presence of chloride ions. Chloride ions result mainly from exposure to salt-laden air. Mumbai being a port city, FOBs and ROBs are especially vulnerable," said an engineer of CR.
