In September last year, NHIDCL and NGI signed a letter of intent related to development and infrastructure projects in the Himalayan region. The challenge facing NHIDCL is to build secure infrastructure in the most efficient way. Therefore, they have engaged NGI to assist with their experience and expertise. Of particular interest is technology for the Norwegian method of tunnelling (NMT).
NGI assists in a gigantic road project
Some of the world's most dangerous stretches of road can be found in the Jammu and Kashmir regions of the Himalayas. Many roads here are closed in the winter, and Indian authorities currently use helicopters to secure supplies to these areas. NHIDCL has therefore launched a comprehensive programme of road and infrastructure development projects in the northernmost areas of India.
NGI's role is as an advisor. Initially, NHIDCL wants to use AEM services (electromagnetic scanning from the air) to see if the rock quality makes it possible to use NMT in the Himalayan mountains. If so, two National Highways delegations from India will come to NGI and learn to gain knowledge of NMT.
The new Austrian tunnelling method (NATM) is currently being used. However, this method is estimated as being about five times as expensive as NMT. As of now, it has been decided to use NMT in at least one of the tunnels to be built.
Introducing AEM technology
Rajinder Kumar Bhasin, NGI's National Highways contact in India and Andi Pfaffhuber, head of EMerald Geomodelling, director for NGI's new spin off company providing services in AEM, were recently in India and signed a contract for the use of AEM technology in four of the tunnels to be built in the Ladakh region of the Himalayas.
EMerald Geomodelling will provide information for the construction of four tunnels with a total of length exceeding 3 miles. The areas range from deep valleys to high mountains, and the highest road pass is 5500 meters above sea level (more than 100 meters higher than Mount Everest Base Camp).
This is the first time this technology has been used in India for mapping ground conditions for tunnels. The technology and surveys make it possible to create geological engineering models. These provide a sound basis for decision-making for further planning of new road routes. The aim is to ensure safe traffic conditions all year round.
The region's extreme variations in terrain, landslide risk and severe snow conditions present great challenges for safe transportation. Existing roads may remain closed from October to May due to existing conditions.
Surveying in such high mountainous areas represents a new approach. Ordinary helicopters cannot be used at such elevations. Therefore, Indian military helicopters will be used for this purpose. Work is expected to be completed this summer and geological engineering models will be delivered in early autumn 2019.