Dam project brings jet grouting to India

One of the highest profile national infrastructure projects in India is the Polavaram dam. It has been on the drawing board for more than 70 years, but since 2015 the approximately US$10 billion project in Andhra Pradesh state has been gathering pace. The main dam itself will eventually span the Godavari River but it is on the two upstream and downstream cofferdams, which will divert water while the main dam is constructed, that Keller India is finishing off a successful jet grouting project.

 Keller India's jet grouting work on the Polavaram dam project

Keller India's jet grouting work on the Polavaram dam project

"Not only have we met the requirements of the client on what is an incredibly important project, but we have also successfully transferred jet grouting technology to Keller India," said Hari Krishna, Keller India director.

The business unit was invited to bid for the project last year. Initially, a sheet-piling solution was proposed, but this was deemed too inefficient due to practical limitations of depth and seepage cut-off. Jet grouting was suggested as the best alternative option, but the technology was only offered by a few Indian firms on a small scale, so Krishna contacted Keller's jet grouting global product team (GPT) for assistance.

"As a global company, Keller can handle the world's largest jet grouting projects and has lots of expertise in this area, so our GPT was able to help us bid for the job," noted Krishna. Expertise also came from all over the Keller world and included jet grouting expert John Willett and master driller Mark Fellows, both from Hayward Baker.

Over three months last year, the team planned every aspect of the job: the mix, equipment, safety, training and execution. After successfully winning the contract from client Transstroy, specialist jet grouting pumps were shipped from fellow Keller company Bencor, and Keller's in-house equipment manufacturer KGS supplied the rigs, spares and mechanics. With the site in such a remote location, Keller had to ensure the team had everything it needed on-site to keep the programme on schedule.

Once everyone was well trained and everything was in place, the team had to work quickly and efficiently to complete everything before mid-June and the onset of the monsoon season. In total, the project has required around 110,000m3 of jet grouting over a 3km stretch, in columns of 2m diameter and up to 20m deep.