The tunnelling industry has witnessed a steady increase in demand from the infrastructure sector over the past few years owing to the growing needs of diverse sectors such as railways, metro systems, roads, hydropower, water supply and sewerage. Alongside, the tunnelling industry has been deploying smart and intelligent features such as integrated tunnel control systems (ITCSs), video surveillance, wireless communication systems, entrance detection control, electrical fire signalling systems, and SOS call boxes in projects in line with the government’s focus on digitalisation. Incorporating smart tunnel solutions helps make existing and upcoming tunnels safer and more cost effective.
Indian Infrastructure takes a look at some projects that have deployed digital and smart solutions in the tunnelling segment…
The Chenani-Nashri tunnel is a fine example of the deployment of state-of-the-art digital and smart solutions to enhance the efficiency of operations. The tunnel, which is India’s longest highway tunnel and Asia’s longest bidirectional highway tunnel, was completed in 2017. It was built in a record four years despite the hilly terrain of Jammu & Kashmir. It is 10.89 km long and equipped with world-class safety features. The total investment in the project was approximately Rs 25 billion. This is the first tunnel in the country that has a fully transverse ventilation system with inlets for fresh air at every 8 metres and exhaust outlets at every 100 metres. In case of increased carbon monoxide and opacity levels inside the tunnel, the sensors automatically restore the ventilation system by opening fresh air and exhaust windows. The tunnel is also equipped with an ITCS that integrates tunnel operation, safety features and electromechanical systems so that the ventilation, fire control, signal, communication and electrical systems are controlled and auto-activated by a single centralised software. The smart tunnel is fitted with an intelligent traffic mechanism, enabling fully automatic smart controls and doing away with the need for human intervention in its operations.
Meanwhile, the Rohtang Tunnel, also known as Atal Tunnel, has implemented various tunnel automation and digital technologies. The tunnel, inaugurated in 2020, has a total length of 9 km and is located at the Rohtang Pass at an elevation of 3,100 metres (10,000 feet). This makes it the world’s longest tunnel at this altitude. The tunnel has a fault-tolerant automation system that minimises the probability of a production failure to nearly nil, playing a decisive role in achieving maximum productivity. Siemens technology has been deployed to provide electrification, automation and digital solutions for local and remote monitoring, connectivity, lighting, ventilation, power distribution and fire safety systems.
In May 2020, tunnel construction work was initiated on the Zojila project. This is a 14 km long road tunnel under the Zoji La Pass in Jammu & Kashmir. Once completed, it will be the largest bidirectional tunnel in Asia. The tunnel has been planned as a smart tunnel. It will be equipped with smart features such as variable message signs, traffic logging equipment and over-height vehicle detectors. It will also have latest safety features such as a fully transverse ventilation system, uninterrupted power supply, emergency lighting, CCTV monitoring, variable message signs, and a tunnel radio system.
The way forward
India still lags behind many countries in terms of digitalisation in the tunnelling sector. Further, the outbreak of the Covid-19 pandemic has resulted in delays in the tunnel designing process, despite the use of digital platforms. There has been a loss in productivity due to physical distancing norms. Mechanised tunnelling involves various critical aspects pertaining to the monitoring of operations and material due to which it has become imperative to introduce digitalisation and automation in the tunnelling process. Further, there is a need to collate all data related to precast segments into a single digital system in order to ensure efficiency in logistical operations. The integration of data related to tunnelling material and equipment through digital means is gaining traction globally as it helps in quality control, documentation, logistics control and factory management.
Going forward, tunnelling projects in India are expected to increasingly deploy smart and digital solutions in order to enhance efficiency in operations and safety, and enable cost savings. In light of the pandemic, solutions such as sensor-based disinfection of tunnels and drone-based spraying systems should be installed for contactless sanitisation. Further, machine learning and other advanced algorithms can also be implemented to monitor social distancing.