The Chunnel

The Chunnel, short for the Channel Tunnel, is not a hidden engineering marvel.  Most are aware that the UK and France are connected via a railroad system in tunnels underground.  Its popularity makes this modern engineering feat no less spectacular.

Throughout history Europe has been shaped politically and culturally by the separation between England and mainland Europe.  The English, while close enough to be apart of European culture were able to develop separately, and use the water as a military defensive tool.  Without the English Channel they probably wouldn’t have developed the naval powerhouse that they did, which in turn would have changed the outcome of many European wars.  It’s hard to imagine how different our world today could’ve been.  On the other hand, the separation was also a hindrance on the business and personal travel between European countries.  Due to the unpredictable weather, traveling by boat was a large inconvenience.

Building a tunnel had been talked about numerous times before it was actually completed in 1994.  People were designing plans since the early 1800s, but due to concerns about national security and expenses, the plans were denied.  In 1984 the French and British government agreed on starting a consultation process for privately funded tunnel designs, and in 1986 a design was agreed upon.

The Building Process

The first task of making the tunnel a reality was finding the best place to start drilling.  The bottom of the English Channel had to be meticulously examined.  It was determined that the lower chalk layer would be the place to begin.

chunnel3

When the actual digging began it was considered a race.  The British and the French both tried to reach the middle faster than the other.  Both sides used the same TBMs, Tunnel Boring Machines.  The machines cut through the layer of chalk and collected the left over spoil, or debris.  The spoil was then transported back with conveyor belts.  The British brought the spoil to the surface using railway wagons while the French added water and pumped it out through pipelines.

tunneling_tbm_diagram_large

While the chalk was being cut away, a layer of concrete had to be applied.  This layer waterproofed the tunnel as well as protected it against the pressure created from the water.

Although the British won the race to the middle, it was a joint effort to connect the two tunnels.  There had been lots of planning using the newest technology to make sure the tunnels were aligned, but it was still an amazing moment when the two tunnels became one.

The Chunnel actually consists of three tunnels, ducts, and smaller tunnels for the necessary equipment, but after the first tunnel was built the light could truly be seen at the end.  When all was said and done the project cost $21 billion.

Travel

England and France have many tourist attractions.  While the Chunnel might not be the main reason to visit either country, it can be the form of transportation you use to get from one to the other.  To purchase tickets between London and Paris visit www.eurostar.com.

Happy travels!

Sources:

http://science.discovery.com/science-technology/10-feats-of-engineering.htm

http://www.pbs.org/wgbh/buildingbig/wonder/structure/channel.html

http://www.eurotunnelgroup.com/uk/the-channel-tunnel/history/

http://history1900s.about.com/od/1990s/p/Channel-Tunnel.htm

http://www.engineering.com/Library/ArticlesPage/tabid/85/ArticleID/79/The-Channel-Tunnel.aspx

http://www.therobbinscompany.com/our-products/tunnel-boring-machines/

http://www.wsdot.wa.gov/Projects/Viaduct/About/Tunneling

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Posted in France, United Kingdom | Tagged , , | 6 Comments

Banaue Rice Terraces

In the Philippines, some 200 miles north of Manila, the ancestors of the Ifugao people created a complex system of rice terraces.  It all started around 2,000 years ago and the terraces are still in use today.    They cover an extensive area of the Cordilleras Mountains.  What makes these terraces so unique and amazing is that they were built by hand at such a high altitude on mountains with such a steep grade.  These terraces truly define the economic and social development of the Ifugao people.

Photo by: jonrawlinson, Creative Commons

Banaue Rice Terraces
Photo by: jonrawlinson, Creative Commons

Intricacies of the Design

The complexity and detail in the rice terraces is astounding.  They were the only structure from the civilization at the time to include stone, as most everything else was made from wood.  The stone and mud walls were used to support all the weight that came from the water needed to flood the terraces.  Each terrace had to be level in order to make sure the rice was watered properly and evenly.  There was an underground conduit designed for drainage, and it was just one of the many devices put into place to regulate the water flow.  They gathered the water from the mountain rainforests and carefully guided it through the terraces.  There are different dams, pipes, and channels to distribute the water equally.

Cultural Impact

Normally I believe the surrounding culture really influences the design of engineering feats, but in this case the terraces heavily affected the culture.  With the rice and vegetables grown being their main source of food the society’s schedule revolved around what needed to be done for the terraces.  The culture had a very cyclical nature to it and followed farming seasons.  Religious rituals accompanied different events and the rice gods became increasingly more important to the people.  While the design of these terraces is impressive it is also amazing how well the knowledge has been past down these last couple thousand years.

Threats

The terraces would not be around today if they were not continuously maintained, and there have been different threats over the years.  Changes in climate have affected the way they have been able to use the water.  Some terraces had to be abandoned due to drought.  Another threat was the spread of Christianity during the 1950s.  Since the maintenance relies on the religious rituals promoting the connection between man and nature, Christianity could’ve been a poison.  Fortunately, the people were able to find a way to implement the tribal rituals with the new religion.  Today the landscape is facing another challenge caused by modernization.  Since a large portion of the younger population is making the decision to move into more urban areas, the terraces aren’t receiving the attention they need and erosion is beginning.  The hope relies on the protection tourism can create.

Travel

Tourism has increased over the past few years and it is rather easy to visit.  From Manila there are many buses that make the eight to nine hour drive daily.  Once in Banaue, it is recommended to use a guide to prevent getting lost and to get the most out of the experience.  There are different inns and places to stay in the villages at the base of the rice terraces.  You can go purely to see the terraces from the viewpoint, but many go for the exquisite hiking the area offers.  The views are impressive, but the hiking is rigorous due to the altitude and climb.  Many recommend training before going to make sure you are in well enough shape to enjoy the trip.   I know the Banaue rice terraces have made it onto my “must see” list.

Sources

http://www.engineering-management.net/ancient-engineering/

http://travel.nationalgeographic.com/travel/world-heritage/philippine-rice-terraces/

http://whc.unesco.org/en/list/722

Posted in Philippines | Tagged , , , , | 4 Comments

Persian Wind Catchers

For our first exploration let’s visit ancient Persia and the unique wind catchers.  Ancient Persia was full of hot days, cool nights, and low humidity.  They needed ways to tame the weather for their own comfort as well as for the storage of water and food.   There were a few simple methods such as: building their homes out of thick mud to increase the insulation and building everything tall to create shade during the day.  A more complex solution was to use nature’s benefits to moderate temperatures with something called wind catchers. There were different types of wind catchers in different locations due to their varying climates.  Let’s take a look at some of these concepts.

Air Intake Designs

The first design we are looking at creates the effect that an electric fan has in your home during the summer: it doesn’t actually cool the air, but it does cause airflow, which makes a cooling effect.  This type of wind catcher consists of a tall tower with one opening facing the direction the wind most often blows toward.  The wind enters the opening and is forced downward and into the main area of the building.  This starts a cycle of moving air throughout the building.

Wind Initiated Outflow designs

There are types of wind catchers that transfer heat and rush cold air through the building.  One type is wind powered and works with an underground water canal called a qanat.  The tower has an opening facing away from the source of the wind.  Due to the moving air outside, the inside air is drawn up and out.  With the air leaving there is a decrease in pressure near the exit and air is pulled in from the other end where there is an opening to the qanat.  This new air is cool from the water, and it cools the rest of the building as it travels through.

Hot Air Escape Designs

When there is no wind blowing there is still a type of wind catcher that is applicable.  This type uses the difference in pressure from hot air and cold air to cool the building.  Since hot air is less dense it rises and will want to escape out a vent in a tall tower.  While this design sounds simple it can cool lower levels to almost a frigid state.

Travel

Now that you understand wind catchers you might want to see them for yourself.  A common place to look would be Egypt or Iran.  I would suggest visiting Yazn, Iran, because that is where some of the tallest and most impressive wind catchers can be found.  However, you may not need to travel far because similar towers can be found across the globe today due to their green design.  The visitor center at Zion National Park has added a wind tower with many similarities to one of the ancient Persian air intake designs.

I hadn’t know anything about Persian wind catchers previously, and I learned a lot from the Circle of Ancient Iranian Studies.  It’s amazing how technology from so long ago can be relevant in new developments today.

Posted in Iran | 4 Comments