Mumbai: Pandemic surges, so does construction of Coastal Road

An illustration shows how fewer pillars will be constructed with the use of monopile technology

The pandemic has gripped the city, but the Brihanmumbai Municipal Corporation (BMC) has managed to focus on the ambitious Coastal Road project. The project, which has many ‘firsts' in its construction, also involves various new technologies which will be used for the first time in the country. This time it is monopile technology.
With the monopile technology, 176 pillars will be erected under the bridge that will be part of the coastal route. Initially three test columns will be constructed using single column technology and the process has just started. The machinery required for this has been brought from Europe and skilled technicians from abroad with practical experience are present at the site.

What is monopile technology

A bridge of approximately 34 metres width and 2,100 metres length will be constructed along the coastal route. Usually, while building bridges in the sea, the pillars are erected in a group pile manner - four pillars are built and considered as one. However, in the monopile technology, a single solid column is erected from bottom to top instead. Accordingly, 176 pillars will be constructed under the bridge.

A civic official said, "If these pillars were to be erected using the traditional multi-pillar method, a total of 704 pillars would have to be erected on the sea level. It would have taken more time and money to use more seabed space. The pillars using single column technology will be erected from bottom to top and they will be 176. As the number of columns has been reduced, the use of the seabed will be minimal and more environmentally friendly and will also save time and cost of construction."

How pillars will be tested

The three test columns will be 2.5 metres, 3 metres, and 3.5 metres in diameter. The total height of these columns from below and above ground will be about 18 metres. The pillars will be erected on the beach road near Bindumadhav Thackeray Chowk on Abdul Ghaffar Khan Road in Worli. And when they are completed by the end of July they will be subjected to different tonnage pressure vertically and horizontally, to measure the load bearing capacity and shock resistance. "The construction work of the actual pillars to be erected at the designated place of the bridge will start after the monsoon, which is after September 2021," said Chief Engineer Suprabha Marathe.