Introduction to Urban Infrastructure: Transport Sector Development

Urban infrastructure defines the framework of a city and its inhabitants and is an important factor in the outcome of a city’s economic growth. To keep up with GDP growth, it is estimated that $17 trillion is required for the Asia-Pacific region to meet this demand by 2030. This includes developing transport such as roads, railways, ports and airports, power, water, housing, sanitation, education and telecommunications.

Local, regional and national economic growth is due to urban infrastructure and approximately 80% of GDP is developed in urban areas. So, developing infrastructure in urban areas is important for the economies of regions and nations. Cities are majorly responsible for the continuous development of the economies of countries but also have a large contribution to the rise of greenhouse gas emissions. They are also prone to flooding, landslides, heat waves and water shortages. So future infrastructure development must have these risks considered to procure a safe environment for people to live and work in.

Railways are a basis for goods and passengers to be transported upon trains which run along the rails. A railway’s infrastructure involves earthworks, bridges, tunnels, steelwork, timber and track system where several disciplines of engineering is required to develop this system. Railways benefit society by transport goods from sources to urban areas for further use in production. For example, transporting iron ore from mines around Newman in Western Australia to Port Hedland where it is transported via ship to China where it is processed and used in production of materials such as a rail. Railways are also used to transport people around a city or across a country which reduces emissions of greenhouse gases compared to if people were using cars as transport.

Overview of a Life Cycle Assessment for Urban Infrastructure Development

Iron ore is obtained though mining through the earth. This is done by digging through a layer of dirt and rocks, and then drilling and using explosives to loosen the iron ore. The iron ore is dug up and placed into trucks which transfer it to a crusher. The crusher crushes the ore into small pieces so that a conveyor belt is able to move the pieces onto a holding pile where it is transferred to another conveyor belt which transfers the ore to another crusher and then to a sorter where it is sorted based on weight. The pieces that are kept are taken to a stockpile where it is further loaded onto trains to be transported away from the mining site. Iron ore mines are usually by the surface so a large hole, about 2km long, is dug to collect the iron. Surface level mines destroy the landscape because of the deep holes in the ground. They may also destroy sacred indigenous sites as there are many places where Indigenous Australians have painted on rocks telling stories. As these mines are usually in rural areas, not many people would care for how the landscape looks because in Australia there is still more areas of wilderness than mines and cities so there is plenty of space for admiring the landscape. Mines can also destroy the ecosystem such as areas below the ground where there is bore water reserves. Also, towns which were populated when large amounts of ore were discovered would empty once the ore is depleted or mining is stopped leaving structures behind. Since most iron mines in Australia have its ore shipped to China for processing, this would be taking away potential economic growth for Australians but since it would cost more to pay Australians than it would to pay Chinese workers, the iron ore is processed out of the country and develops the economy of China instead.

The iron ore is then transferred into a blast furnace where it is smelted to form molten iron. A by-product of this smelting include slag which is a waste material used to make tarmac or railway ballast. Another by-product are the gases produced during the smelting process; they are used for heating in further processes such as boiling water to produce steam which powers the rolling mills. However, the gases would have to be released from the system at some point and would spread into the atmosphere causing air pollution which is bad for the environment as it contributes to global warming.

The molten iron is then dropped into a ladle which is then combined with carbon and manganese to create a stronger alloy called steel. It is then poured down a ceramic tube, limiting exposure to oxygen and shaped into blooms, which are long rectangular shaped blocks. The blooms are cut, reheated to soften them and rolled through a rolling mill, lengthening them. These longer pieces are squared off, again reheated and passed through more mills which shapes them into a ‘T’ shape. Once cooled, the rails are rolled once horizontally and then vertically to flex the steel into a straight rail. These rails are cut into its desired length and sent off to the desired railway site to be integrated into a railway track. The process of forming rails from molten iron doesn’t have many negative effects to the environment as no harmful by-products are produced from this process. However, in order to heat the steel bars before rolling, it requires the gases produced from the blast furnace and once the gases cool it no longer becomes useful and would be removed from the system and most likely into the atmosphere which pollutes the air. The parts of the steel that have been cut off due to squaring the ends are placed back into the blast furnace to be remade into molten iron.

To implement the rail into the railway track or to replaced old rails it needs a clear path for the rails to be placed safely so vegetation might be removed, and fauna would be relocated to a safer place. For any non-flat earth where the railway is planned to be, would have to be dug or filled in the create a flat surface for the rails to be placed. Embankments and retaining walls are built around the track to stabilise the ground, a drainage system will also be required to prevent the railway from becoming submerged in case it rains. Bridges and tunnels may also be required if the railway transverses across a valley or through a mountain and would be too expensive to place dirt or dig up the mountain to allow the track to pass through. The track bed is made from layers of crushed stone called a ballast and is flattened and stabilised, sleepers are the fixed at regular intervals and the rails are placed on top of them and connected. Electricity is required for the trains to operate so power lines are built along the railway line and connected to a nearby power station to power the trains. Removing vegetation for the railway would have a severe impact on the flora and fauna because less trees means the soil would lose its fertility and less carbon dioxide would be turned back into oxygen, also the animal life would be less prominent in the area and would either become more densely populated elsewhere or perish. The electrical wires above the train are vulnerable to stormy weather so if the wind is strong enough it may disconnect the overhead wires and can spark and set fire to any nearby combustible materials which could result in damage of the railway system, its users and nearby structures.

At the end of a railway track’s life, they are usually abandoned if the route is no longer used. So, the tracks are left behind for grass and trees to grow and cover the tracks, making it even harder to access if collecting the components would ever be considered. Since it is too expensive to employ workers to retrieve unused rails, some organisations have converted the abandoned railways into walk and cycle trails for people to walk or cycle along. This can encourage people to go outside and admire the history of the railways and if there is a cost for people to access the trails, it can provide a source of income for local communities.

Conclusions and Recommendations

A project engineer works as a manager of engineering projects and manages the employees, budget and time schedule of the project as well as risk management and communicating with contractors . They require skills such as organisational skills to time manage and to make decisions on the priorities of the project, problem solving abilities as problems and setbacks may occur and require finding solutions as efficiently as possible. Commercial awareness is another skill as they must comply with the budget and schedule for each project, communication skills are needed to inform workers on what needs to be done and understanding what has been done as well as giving contractors an understanding of progress throughout each project. In the infrastructure of a rail, a project engineer would have to track the progress of iron ore deliveries to the rail making factory for it to be turned into steel, they would also have to make sure that the steel making and rail making has been going to schedule. They would also manage where each batch of rails goes and the cost of making each batch, so it stays within the budget. They would also oversee the construction of the railway making sure it conforms to the time schedule and cost.