Sahar Road crossover tunnel, India

Project type:

• Subway tunnel 

Application: 

•  Permanent spray concrete linings

Partners: 

•  Owner: Mumbai Metro Rail Corporation
•  Contractor: J Kumar –CRTG (JV)
•  General consultant: MAPLE 
•  Sub-contractor - Endacom and Normet 
•  Consultant – Bedi Consulting Ltd

The challenge

As the tunnel runs through the busy heart of Mumbai, speed and convenience was of the essence. To facilitate the job and to save time, Metro authorities decided to apply a permanent spray concrete lining in the Sahar Road crossover tunnel (227 m / 745 ft) long.

The solution

For this particular section of the tunnel, contractors used C32/40 concrete reinforced with 30 kg /Cum Dramix® 4D 65/35 BG steel fibers for the permanent sprayed concrete lining.  By choosing for a steel fiber reinforced design, the contractor significantly reduced complexity and material cost by eliminating traditional reinforcement. It was the first time for the company to use SFRC for this particular application rather than the traditional concrete reinforcement.