Word Highest Bridge: Chenab Bridge Arch Closure Completed

The Indian Railways recently completed the arch closure of the world highest railway bridge, Chenab bridge. The bridge is a part of Udhampur-Srinagar-Baramulla rail link project.

About the Arch Closure

• Arch Closure was one of the most difficult parts of the bridge.
• The Arch consists of steel boxes. To improve the stability of the arch, concrete is to be filled in the boxes. The two main benefits of using concrete filling are as follows:
  • The filled in concrete assist in controlling wind induced forces.
  • Also, using concrete filling removes the necessity of internal painting.
• The overall weight of the Arch is 10,619 metric tonnes.
• “Tekla” software was used for structural detailing of the arch.
• The steel used in the arch can withstand -40 degrees Celsius.
• The Arch span is 467 metres and arch length is 480 metres.
• The Arch of the bridge is highly important to sustain vertical loads.

Chenab Bridge

• The Chenab bridge is located in Reasi district of Jammu and Kashmir. The height of the bridge is 359 metres.
• The deck height, that is, the height above the river bed is 359 metres. The length of the bridge is 650 metres.
• The construction of Chenab bridge was declared as a national project in 2002.
• The most challenging aspect of this rail link was the large number of tunnels and bridges to be constructed in the rugged mountainous terrain. Of all this, the most difficult part was to cross the deep gorge of Chenab river whose arch closure has now been completed.
• Another small arch bridge proposed in the same route is Anji Khad bridge.

Standards used in Chenab Bridge construction

The arch rail bridges at such heights require number of additional parameters such as global stability, fatigue, composite action, second order effects, etc. In order to achieve these parameters, Indian Construction Standards such as Indian Road Congress, Indian Standards and Indian Railway Standards were inadequate. This is because the Indian Railway Standards are primarily intended for simply supported bridges up to 100 metres of span. The span of Chenab bridge was greater than this. Thus, international standards such as International Union of Railways, British Standards were supplemented to construct the Chenab bridge.

Month: Current Affairs - April, 2021