The Channel Tunnel is the rail tunnel connecting Great Britain with continental France commonly known as the Euro Tunnel or the Chunnel. Below lies the English Channel. This transport is capable of taking people and goods across easily without stress from one country to the other within less than half an hour. It runs across the English Channel and is 50 KM long. Six years into its construction, the Channel Tunnel was opened in May 1994. The world’s longest underwater tunnel is this one. It has evolved over the last 25 years into a lifeline physical connection between UK and continental Europe as well as the most symbolic one, especially in the aftermath of Brexit. In the article of The Article Heaven we understand how Euro Tunnel is planned and their challenges being occur while construction.
Overview of the Channel Tunnel
Crossings of the English Channel by boat or ferry had been a ghastly experience for many years. Even the most hardened tourist could be touched by seasickness caused by the choppy waves and possibly inclement weather. Hence, it is hardly surprising that ideas concerning an alternative route across the English Channel began to be designed as early as 1802.
Early Dreams and Visionary Beginnings
It is certainly no novel concept that digging a way through the under the English Channel. Designs conceived in the early years of the nineteenth century aimed to connect Britain with the continent of Europe, and several ideas were proposed by engineers through underwater floating tubes and tunnels that were designed for horse-drawn vehicles; yet, they were only limited to the lack of technology in those early days.
Tunnel excavation method
- Since 1988, all tunnels have been dug using TBMs. There are six that come from the UK and five from France that have dug them.
- The service tunnel was constructed for the first time using TBMs. As a result, engineers were able to establish the actual status of the ground.
- The two crossover caves were formed by access from the service tunnels. Following through the caverns, TBMs working on the principal tunnels descended into the chalk to carry out their further work.
- The French end has wetter ground than the British end. As a result, British TBMs excavated more tunnels, but French machines worked more slowly.
- Two tunnel lining methods were used by the engineers: precast concrete rings and cast iron sections that were welded together.
- TBMs extracted vast quantities of chalk. On the French side, it was crushed with water, and taken inland behind a 37-meter-high barrier. On the British side, engineers used the chalk to create an acre of landscaped platform in Dover at the foot of Shakespeare Cliffs.
Fears of an invasion
More than 180 years before its actual conception and excavation commenced work by French and British laborers in 1988, the tunnel was envisioned as such. French engineer Albert Mathieu-Flavier was the first to propose a subterraneous link across the English Channel between France and Britain already in 1802, but instead of horses pulling a carriage, he proposed creating a man-made island in the English Channel.
Approx. 50 KM tunnel was built in six years by 13,000 workers, 23.5 of whom were underwater, making it the longest tunnel of its sort in the world. Unavoidably, that degree of engineering and manpower was costly; estimates in 1994 placed the costs at £4.65 billion (about $7.2 billion), an astounding 80% rise above initial projections.
Major obstacles that face the construction of the Euro Tunnel:
The project was far from being a mere test of technical skill: it was a battle drawn each day against logistical, technological, and environmental forces. There are some Channel Tunnel Construction Challenges that was faced:
- Water Pressure and Leaks Digging: Under a body of water as big as the English Channel was extremely dangerous. Thousands of tons of pressurized water drowned on top of the tunnel. They used waterproof linings and sophisticated sealing techniques to prevent leakage through the linings. Leakage into the tunnels during construction was always induced, not with standing all these precautions.
- Geological Conditions: Complex geology conditions abound in the English Channel where in diverse rock and soil types exist. Hence, required extensive geologic survey research and construction techniques modifications, especially in areas of soft clay and chalks.
- Funding and Budget Overruns: The cost-beyond-estimated expenses were the issues that surrounded this costly attempt at building the Euro Tunnel. The severe financial problem of the project was caused by the inefficiency in raising funds and managing the budget.
- Ventilation and Safety: The tunnel’s cramped design caused ventilation and safety problems. Engineers conceived a ventilation system that could regulate airflow, remove heat, and retain quality air. The safety design included the central service tunnel, fire-resistant materials, and emergency exits: it provided rescuers with access and ways to escape quickly.
- Social and Environmental Issues: The environmentalists complained about the possible knock-on effects on coastal habitat and marine life. Very stringent steps were taken to minimize disruptions related to construction work as a corrective measure. Vibration, noise, and other impacts were monitored with great care and kept within very reasonable limits.
- Logistics and Coordination: The large workforce, transportation of supplies, and coordination from one country to another of thousands of workers and hundreds of contractors along with their equipment were some of the major logistical challenges that came up.
- Collaboration Between Two Countries: There needs to be close cooperation between France and the United Kingdom in developing Euro Tunnel. Coordination was difficult because of some differences in languages, technologies, and laws. Cooperative planning groups and regular communications helped overcome this problem by making sure that everybody was working toward the same objectives.
Also Read : 10 Interesting Channel Tunnel Facts
Opening of the Channel Tunnel
The first run through the channel was completed by 10 December 1993, finishing the test of the entire Channel Tunnel. The Channel Tunnel formally opened on 6 May 1994, following some minor adjustments. The Channel Tunnel finally saw its completion after six years of construction and $15 billion (other estimates have that figure as high as $21 billion).