Construction is currently underway on the Patna Metro subway project, located in the state of Bihar in northeastern India. Apart from subway lines and stations, the project also includes elevated railway routes along with train depots and the associated infrastructure.

Bauer Engineering India Pvt Ltd was awarded the contract for diaphragm wall work at four stations as well as for a retrieval shaft. “We are excited to contribute to this groundbreaking project. Our diaphragm wall elements act as solid and permanent foundations on which the new subway stations will be constructed,” said Yogeshwaran Purushothaman, project manager at Bauer India.

The work started in November 2022 and is expected to be completed by March 2024. Over this period, a total of 636 diaphragm wall/barrette elements will be constructed for all four stations. As an impermeable/structural retaining structure, they provide stability and structural support. Among other equipment, a Bauer GB 34 hydraulic grab, a Bauer GB 50 and a DHG grab on a Bauer MC 96 duty-cycle crane are being used.

In June 2023, Bauer India set a record on this project as the team achieved the deepest barrette foundation element ever constructed at Patna Metro. It was installed at a depth of 75 m using a hydraulic grab. “This is a milestone in the history of Bauer India,” said Mr Purushothaman. The remaining diaphragm wall elements will be installed up to a depth of 55 m.

The Bauer India team has faced a range of challenges in the process. For instance, the different geological soil profiles across the four sites and retaining verticality during work require the utmost attention. What’s more, all work has to be executed under very limited spatial conditions within the city. “This project is an absolute highlight for the entire team,” remarked Mr Purushothaman. “We are unbelievably proud and motivated to master all the challenges involved.”

All images: Bauer Group