New Delhi: India is the seventh-largest country in the world, with a total area of 3,287,263 square kilometres (1,269,219 sq mi). It has a land frontier of 15,200 km (9,445 mi) and importantly a coastline of 7,516.6 km (4,671 mi).
This is just an indication of how much India is exposed to global warming which is set to severely impact buildings, dams, roads, bridges, automobile sector, railway sector, energy sector and petroleum sector.
Global climate change is one of the most important concerns for world governments and is a major research subject for the scientific international community with the participation of multi and interdisciplinary groups. Two fundamental reports – the United Nations Intergovernmental Panel on Climate Change (IPCC) and the N. Stern, The Economics of Climate Change, 2007 Cambridge University Press, UK, outlines parameters that will affect infrastructure, temperature change, atmospheric moisture change, sea level raise, wind, desertification, pollution and inclusive biological infestation.
Temperature change is gradually resulting in extreme climate, changing the periodicity of climate cycles. Such extreme climate events are bringing detrimental effect by way of corrosion and also bio-deterioration. This is also damaging both metallic and non-metallic materials used in infrastructure construction.
Many studies have elaborated the impact on structures due to global warming and their exposure to corrosion.
Reinforced concrete (RC) structures are subjected to environment actions affecting their performance, serviceability and safety. Among these actions, chloride ingress and carbonation lead to corrosion of reinforcing bars that reduce the service life of RC structures. Evidence indicate that carbonation and chloride ingress are highly influenced by environmental and climatic conditions of the surrounding environment – atmospheric Co2 concentration, temperature and humidity.
Zinc, through galvanization process, protects steel from rusting that enhances the lives of buildings, houses, bridges, railways, ships, defence equipment, highways, and airstrips to name prominently, though there are a number of other usages of Zinc that protect steel from rusting.
Sunil Duggal said, “Awareness is the key to build a galvanized Indian economy. People do not understand the difference between ‘steel’ and ‘galvanized steel’. Galvanized steel increases the life of steel and gives life to not just industrial sectors but also house-hold sector. Galvanization is a layer of protection to safeguard steel from rusting. Globally people are understanding that use of galvanized rebars can increase the life of their houses that can withstand many risks. Infrastructure at coastal areas are at the maximum risk due to humidity and constantly changing climate. Galvanized rebars protect pillars and hold construction. Galvanization of steel used in car body enhances the life of vehicle multi-fold – your recurring expenditure on repairs decreases and your safety increases. The new mega infrastructure development that is happening in India today, with the use of steel, should only use galvanized steel for strength and long life.”
Sunil Duggal reminded of the massive cloud burst that happened in Uttarakhand in 2013. He said, “I remember in the year 2013, due to cloudbursts in the state of Uttarakhand, the flash floods in river Ganga and landslides washed away thousands of lives. The Kedarnath Bridge at Sonprayag was also washed out due to heavy floods. The death toll and destruction was so massive that it left the region devastated. Subsequently, a Bailey bridge (a portable, pre-fabricated, truss bridge) was built by the Border Roads Organisation, limiting the traffic to one way and a maximum load of 12 tonnes at the most. But June 2015 saw more floods and this bridge was also washed away.
Since the Temple is 3500 feet above sea level and is situated in a challenging topography, the construction of a stronger flawless bridge required more than 3 years to build. Further, since the bridge was to be built in such difficult conditions, it would have been impossible to regularly protect or maintain. It was finally decided that the new bridge has to be made of galvanized steel to ensure that it does not collapse.
The galvanized bridge was shipped in containers from the USA, completed and became operational in an incredible 45 days. In the new bridge, all the panel chords, diagonals, verticals, raker, reinforcing cords along with all the structural beam members and flooring were hot dip galvanized. This bridge could have been ‘Made in India’.
He gave another example of Bandra Worli Sea Link. The Bandra Worli Sea Link is the first and the longest sea link bridge in India. It is an 8-lane cable-stayed bridge, spanning about 5600 meters in length and towering to a height of 126 meters. Executed at a cost of Rs.16.5 billion, the material used in the construction project had to meet quality regulations and standards considering an average daily traffic of 37,500 vehicles.
“Infrastructure like bridges are extremely vulnerable to rust and corrosion due to their proximity to marine salts and moisture. One of the rust prevention methods for these structures is to provide a barrier coating by galvanization, galvanization by Zinc” he said.
The quality and reliability of steel wire ropes was a crucial factor in the construction of the bridge since the steel wires are required to support the cable stay bridge. The bridge stands strong with support of high-strength galvanized steel cables, rigorously tested before being put to use. Over Rs.90 million is spent on illuminating the sea link. Many countries came together and decided to build this bridge to ensure that it stands tall in any condition. India, Egypt, China, Canada, Switzerland, Britain, Hong Kong, Thailand, Singapore, Philippines, Indonesia and Serbia deliberated extensively on safety and longer life of Bandra Worli Sea Link Bridge and the importance of using galvanized steel.
Sunil Duggal is of the opinion that in India, for environment protection, government has listed several laws. Many Acts have been passed in Parliament. But what about the damage to environment and economy through rusting and corrosion – “Creation of junk is destruction of environment and economy. Corrosion eats around $600 billion infrastructure a year which is about 6% of GDP” he says.
“Coastal salts can create a corrosive environment for any infrastructure across the world, the reason being humid and saline climate. When steel reinforcement corrodes, the corroded product occupies more than three times the volume of the original steel, exerting great disruptive tensile stress on the surrounding concrete, leading to further cracking, more weather access and further corrosion. According to the American Institute of Architects, it is essential to use hot dip galvanized steel, to make such coastal infrastructure decay resistant” he said.
Speaking about the recurring expenditure being incurred by Indian Railways on changing of rails, fishplates and other infrastructure. The fourth largest rail network in the world, Indian Railways, comprises 125,000 km of track length over a route of 67,312 km. More than 50% of the route is electrified. Indian Railways has about Rs 1.35 Lakh bridges and about 800 are most important.
Sunil Duggal said, “Indian Railways sector is a major concern since rusting and corrosion of the infrastructure is becoming a worry for safety of passengers. Almost all the infrastructure of Indian Railways is exposed to humidity, dust and extreme change in climate. It is already struggling due to huge expanses in replacement and repairing. The annual loss due to pre-replacement of corroded rails is huge about Rs. 440 crore. Many accidents have been attributed to corrosion of “Fish-plates”. Experts have estimated losses of almost 4% of GDP per year on account of corrosion which may be avoided if the railway tracks are galvanized. Corrosion reduces the life of rail to nearly half its expected life.”
Car makers in Europe, North America, Korea and Japan have been using galvanized steel for body panels for decades and provide anti-corrosion and perforation warranties for a minimum of 10 years. More than 60% of the cars in India have surface rust which reduces steel strength and the life of the car.
“Globally the top brands in cars started galvanising various parts of the cars including the body to fight corrosion issues. This brought safety to the cars and protection to the environment and strengthened the economy. By 1987, what became standard was a 10-year perforation and five-year cosmetic warranty from all the North American, European and Japanese automakers for vehicles sold in the North American market. Indian car manufacturers’ use about 3% galvanized steel for domestic market. However, the same Indian car manufacturers use over 70% galvanized steel for the same models which they export to markets in Europe, Asia and Africa, produced from the same stamping and assembly facilities.”
He is of the firm belief that “Indian consumers are not getting it, because they are not demanding for. It is their direct loss.”
“India is producing about 100 million tonnes of steel but surprisingly less than 1% is galvanized, which is just about 8 million tonnes. On the other hand we are importing 1.44 million tonnes of galvanized steel from China, Korea and Japan. We are increasing imports but not producing galvanized steel within the country” Sunil Duggal says.
The global galvanized steel market for the industrial sector was valued at around 56 million tonnes in 2015 and is estimated to grow at a CAGR of about 5% by 2020. America alone produced 4.5 million tonnes of galvanized steel in 2016, which is 30% more than what it produced in 2012. There is a focus for building long lasting infrastructure.
He finally says, “Galvanization of steel will add to Make in India and Sustain in India”. We might be making over-bridges, railways bridges, roads, high-rise buildings, railway tracks, fish plates, metros, electricity networks, ships, and automobiles, and using millions of tonnes of steel. But for how many years are we making them sustain is a point of contention. If our vision is long term, then the infrastructure also needs to sustain even longer.
