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Obstacles faced in the initial stages

The implementation of the proposed bridge took over a year to initiate due to several hurdles and precautionary measures that had to be considered during the planning of the bridge. Construction of a new major bridge so close to an existing bridge was a very difficult task as far as sinking of the wells was concerned. Moreover, it has been constructed only 50 to 60 metres downstream of the existing Saraighat Bridge.
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Besides, an operating oil pipeline also runs very close to two new wells of the new bridge. Oil India Ltd. (OIL) had expressed inability to shift the pipeline considering many factors, including cost and time. However, all the problems arising out of such factors were handled successfully but consumed due amount of time that stretched close to two years.

According to reliable sources the design was made by IIT, Delhi and SPAN but there was a mistake in the design of the bridge which was later handed over to Mott Mc Donald Company Pvt. Ltd. for redesigning. “The total length of the bridge is 1,493.58 metres and comprises of a single girder which should otherwise have 13 girders. The cantilever construction method that has been used will form the continuous girder. The speciality of the bridge is that it is 50 to 60 metres downstream from the existing Saraighat Bridge and there is only a 24-metre gap between the two bridges which can be risky. But with the new technique and special protection the risk had been mitigated,” a highly placed source informed G Plus.

It was also mentioned that floods and high currents reduced the working period for the construction of the bridge considerably. Every year, the working period was reduced to only about six to seven months due to such factors.

Originally, only the main bridge and the grade separator were considered while planning the project. But later on, additional work of signal-free crossing at Jalukbari point was also added to the original scope of work as well as a flyover at the junction point of the road from Hajo. These increased the cost of the project considerably compared to what was estimated originally.

Now, while the major works related with the project are completed, railings, crash barriers, mastic, bituminous carpeting of the main bridge and flyovers, earth work and pavement works in the process of completion.

Rainfall activities during August and September last prevented the laying of bituminous carpet over the girders. Rains also hampered construction of the approach road and earthwork, sources said. The NHAI also faced problems of land acquisition, obtaining forest and environment clearances and shifting of public utilities like telephone and electricity poles which added to the delay in construction of the bridge.
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Construction minutiae

The bridge will be able to bear the highest prescribed load as per the Indian Road Congress specification. When asked to explain the uniqueness in its construction, sources said this bridge is made of a single girder, which is resting on eleven wells and two pile foundations on high bank – one on each of the banks of the Brahmaputra.
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When asked to explain the technique applied in constructing this single girder, sources said the girder was initially constructed as cantilever girders from each pier and then all ends of the girders were joined together to produce a continuous girder, sources said.

A common way to construct concrete cantilever spans is to counterbalance each cantilever arm with another cantilever arm projecting in the opposite direction, forming a balanced cantilever; when they are attached to a solid foundation, the counter balancing arms are called anchor arms. Thus, in a bridge built on two foundation piers, there are four cantilever arms, two of which span the obstacle, and two anchor arms which extend away from the obstacle. Because of the need for more strength at the balanced cantilever’s supports, the bridge superstructure often takes the form of towers above the foundation piers.

“The DPR suggested that there would be a reinforce earth in the main carriageway from grid separator to the approach which can be risky with the high seismic force. Therefore, shock transmission units have been fixed to block the seismic force. The design also suggested that the well should go up to -11 levels which is not safe and we decided to take it to -16 levels,” the source added.

The remaining work of reeling and crash bearer will be completed before 31st December including layering the bridge with bitumen. One of the most important features is that the Jalukbari Rotary will be signal free and will have interconnecting flyovers, one underpass and sleep road. The signal free crossing means that the vehicles coming from all the four directions will not collide with one another and can run in their own direction without having to halt. “A signal-free crossing has also been set up where there are three loops and ramps. The vehicles passing from each side can pass through the loop without hampering the traffic at any time,” the source added.

After the construction of this project, a major missing link in the state will be eliminated. Places like Baihata Chariali, Sipajhar, Mangaldai and a few others will become satellite townships of Guwahati, reducing the pressure on the city itself. Besides, a new green Guwahati can be created in the north bank housing an additional population of two lakhs with provisions of green industrial, commercial, educational and IT hubs that will make the city ready for the Act East Policy.
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Construction time-frames elsewhere in India
Bandra-Worli Sea Link cost Rs. 16 billion bridge, is officially called Rajiv Gandhi Sea Link and was built by the Hindustan Construction Company. Construction began in 2000 and the first 4 of the 8 lanes were opened to the public on 30th June, 2009. All eight lanes were opened on 24th March, 2010.
Mahatma Gandhi Setu - the longest river bridge in India. Over the river Ganges it connects Patna to Hajipur. The construction of the 5,750-metre bridge began in 1972 and was inaugurated in May 1982.
Chatrapati...
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Shivaji Maharaj Bridge in Nashik, Dwarka - 2nd longest road bridge in India. Construction began on 4th January, 2010 the 6.1 km bridge was approved by Atal Bihari Vajpayee in 2002 and was opened on 14th June 2013.
Vidyasagar Setu in Kolkata - the longest cable-stayed bridge in India. Links Kolkata with Howrah. Total length 823 metres, Vidyasagar Setu is the longest cable–stayed bridge in India. Construction began on 3rd July 1979, and the bridge was commissioned on 10th October 1992.
New Yamuna Bridge in Allahabad - 3rd longest cable-stayed bridge in India. Construction of the 260 metres bridge began in 2000 and was ready by the end of 2004.

In The Pic You can see Red Hot LHB Train on the Old n Gold Mighty Saraighat Rail n Road Bridge but Which one of these
12235/36 DBRG Rajdhani
12435/36 DBRG Rajdhani
12423/24 DBRG Rajdhani
12519/20...
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KYQ LTT AC Express
12551/52 KYQ YPR AC Express
Leave out
KYQ BGKT Express
KYQ SVDK Express
Which one of these is in the Pic