‘Daylighting’ achieved ahead of deadline at Kasara tunnel

 

 

 

It was a red letter day at the Kasara road tunnel of Samruddhi Mahamarg as daylighting breakthrough was achieved in the 7.78 km and 7.74 km tubes that would provide a smooth by-pass to mighty Sahaydri mountain. The development is no mean task, as the feat was achieved with Zero rate of accident and in process M/s Afcons also beat the deadline by miles that made the success double sweet. Tunnel construction is part of package-16 of expressway project and entrustment of task to M/s Afcons reinforces the company's position as a leader in execution of mega infrastructure projects in the country. With excavation work complete, now one can travel through either of the tube enabling faster movement to either end of men and material that would help in wrapping up tunnel work way ahead of schedule. Package-16 of Samruddhi Mahamarg is beset with challenges and it encompasses parts of entire 56 packages incorporated in one, including inter-sections, balanced cantilever beam, cut and cover part, two tall viaducts and not to mention the biggest challenge, the twin-tunnels.

 

The project is lined-up for early finish, perhaps by year end as now work of construction of concrete road remains the only task and that would be completed earlier than the target, said Shekhar Das, Project Manager, M/s Afcons. The achievement is not a mean task given the dynamics of the project, right from its scale to overcoming challenges of nature and not to mention outbreak of COVID-19 pandemic in between, said Satish Paretkar, Director, BU Head, Hydro & Under Ground Works, M/s Afcons Infrastructure Limited, a Shapporji Pallonji Group company. "The Kasara tunnel project is phenomenal owing to several innovations that we have incorporated in its design to bring about highest level of safety", said Paretkar, a name to reckon with in tunneling and under ground construction projects in country today. Perhaps the best part of the project is Inclined shaft, an engineering feat as the road traverse in steep upside gradient, to adjust the 350 meters gap in two sides, the Kasara and Igatpuri.

 

The shaft (9.0 Dia x 8.5 m height) and connects to two vertical tunnels (17.61 m Dia x 9.12 m Height) and inside cross-passages are provided at 26 places between two tubes is provided one each at 300 meters gap , just in case there is a jam then same could be used to divert the traffic, Paretkar stated while providing glimpse of the project. The ventilation shaft is another beauty of the tunnel incorporated to provide continuous air flow and same has 70 m depth while length is of 504 meters. The factor was applauded by Anil Kumar Gaikwad, Joint Managing Director, Maharashtra State Road Development Corporation (MSRDC), when he said that M/s Afcons managed to keep within the tight time schedule has eased our worries now. The tunnel work on the expressway project was most critical and everyone kept fingers crossed when work started on September 3, 2019, and it is to be noted that Igatpuri where the site is located receives highest rainfall in entire Maharashtra, about 3000 mm, that made the task more challenging. Yet completion of excavation mean the major work is over.

 

A ceremony was held in the longest road tunnel of Maharashtra in presence of team of MSRDC officials including Gaikwad who specially made it a point to inspect the progress and express satisfaction at speed of execution. The two stretches one of 7.78 km and other of 7.74 kms tunnels would held motorists by-pass the treacherous Kasara ghat on Nagpur-Mumbai route and in process cut down the risk involved in travel on the route. Now nearly an hour is required to negotiate the hilly terrain where road levels drops down or moves up in steep direction making driving a quite difficult and risky. But the twin tunnels would enable speed of 120 kms and one would be criss-crossing Igatpuri to Vashala in a jiffy, five to seven minutes to be exact, said the company officials executing the project. A shade roofing was designed on Igatpuri side to overcome challenge of continuous rains and this would avoid ingress of water inside the tunnel. The span of the roofing covers 0.2 km part in either tube.