June 9, 2015
Sustainable Engineering
Applied to the Inca
Infrastructure
Priscila Gomez
Robert Leyva
Karla Muro
INDEX
1. Introduction .............................................................. Error! Bookmark not defined.
2.
Machu Picchu Life Cycle Assesment .......................... Error! Bookmark not defined.
2.1 Goals and Purpose ..................................................... Error! Bookmark not defined.
2.2 Life Cycle Inventory .................................................. Error! Bookmark not defined.
2.3 Life Cycle Impact Assesment .................................... Error! Bookmark not defined.
2.4 Interpretation .............................................................. Error! Bookmark not defined.
3.
The Guardians House Life Cycle Assesment ........7Error! Bookmark not defined.
3.1 Goals and Purpose ................................................. Error! Bookmark not defined.
3.2 Life Cycle Inventory .............................................. Error! Bookmark not defined.
3.3 Life Cycle Impact Assesment ................................ Error! Bookmark not defined.
3.4 Interpretation .......................................................... Error! Bookmark not defined.
4. The Kallanka Life Cycle Assesment ........................ Error! Bookmark not defined.
4.1 Goals and Purpose ................................................. Error! Bookmark not defined.
4.2 Life Cycle Inventory .............................................. Error! Bookmark not defined.
4.3 Life Cycle Impact Assesment ................................ Error! Bookmark not defined.
4.4 Interpretation .......................................................... Error! Bookmark not defined.
5.
Perspectives from the Different Engineering Disciplines ..................................... 10.
5.1 Industrial Engineering.......................................................................................... 10.
5.2 Civil Engineering ................................................................................................. 11.
5.3 Mechanical Engineering ...................................................................................... 11.
6.
Conclusion ............................................................................................................. 11.
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1. Introduction
Machu Picchu was the last Incan city and was constructed around 1450 during the Inca
Empire. It is located about 80 kilometers from Cusco, Peru. The city was covered with
vegetation except for the cleared agricultural terraces and clearings used by the farmers
as vegetable gardens.
It is possible to recognize that the 12 principles of Green Engineering and the
methodology of Life Cycle Assessment have been applied by the Incas when
constructing the city of Machu Picchu.
It is amazing to observe magnificent
infrastructures that were built many years ago without having any type of technologies.
Incas were great and intelligent engineers and architects, but they did not document the
engineering concepts used and applied by them. It will be our team’s objective to
evaluate how the concepts of Sustainable Engineering and the Life Cycle Assessment
were applied in the infrastructure of Machu Picchu, The Guardians House, and The
Kallanka.
2. Machu Picchu
After our visit, we could notice that Machu Picchu is a very earth friendly construction.
It is hard to find actual information on how the Incas actually constructed this city.
After the observations made to the Inca infrastructure one can notice that the Incas
applied some of the 12 Principles of Green Engineering. These 12 principles help
maximize sustainability by providing a structure that creates and assess the elements of
design relevant. Some of these principles will be briefly discussed giving some
examples to demonstrate how the Incas applied them.
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Principle 3: Design for separation
This principle is clearly applied by
the Incas in their constructions since
separation
operations
and
were
purification
designed
to
minimize energy consumption and
Figure 1. Machu Picchu
materials use. For example most of
the windows from their constructions were placed in a way where they could take
advantage of the sun. This was also applied when constructing their terraces for
agriculture. Another thing is that they knew what type of seeds to plant depending on
the land.
Principle 4: Maximize mass, energy, space, and time efficiency.
This principle recommends to build products that can maximize mass, energy, space,
and time efficiency, and is what the Incas did. They knew the problems that a steep
geography and rainy could face such as the risk of landslides that nowadays are still
producing disasters. That is the reason why it was fundamental to ensure an adequate
foundation and drainage from all that it was going to be constructed there. In order to
ensure that all constructions had good foundation they built solid dikes and walls that
will go under ground filling compartments with rocks and rubble. This way will
facilitate and give a good drainage of the abundant rainwater, avoiding standing water in
streets and squares, as well as sliding slopes and buildings collapse.
Principle 5: Output-pulled versus input-pushed
Principle 5 was also applied by the Incas since they constructed their agriculture
terraces according to the slope of the mountain minimizing waste of energy or raw
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material. For this they had to locate water sources. These were found between Huayna
Picchu to the north and the mountain of Machu Picchu to the south. This collects water
filtrated from the land then it runs by the hillside, channeling among its crevices until it
emerges again in a spring. To take advantage of this spring, a permeable wall over 14
meters was constructed supported on the hillside collecting water that will ooze into the
slope. At the base of the wall, a ditch collects the water dripping and flowing from the
wall, extending the ditch on a channel that carries water to the city, and that also goes
through the agricultural terraces.
Principle 6: Conserve complexity
It was easily recognized that the Incas in their Machu Picchu infrastructure applied this
principle since everything that they built was constructed according to the slope of the
mountain. They tried not to harm nature (Pachamama). For example if large stones were
in the middle of the area they chose to construct they will build around those stones.
One example is the Temple of the Sun.
2.1 Life Cycle Assessment
Life Cycle Assesment is a technique to assess environmental impacts associated with all
the stages of a product’s life from cradle to grave which means from raw material
extraction through materials processing, manufacture, distribution, use, maintenance
and disposal or recycling. In order to perform a Life Cycle Assesment four phases have
to be taken into consideration, these are: Goals and Purpose, Life Cycle Inventory, Life
Cycle Impact Assesment, and Interpretation.
A Life Cycle Assesment will be
performed to the city of Machu Picchu
2.1.1
Goals and Purpose
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The main purpose for the construction of Machu Picchu was to have a temple for the
nobles that could be resistant to natural events such as earthquakes and rain. It can be
said that it was also constructed for farming, water harvesting, drainage and irrigation,
and temperature regulation for crops.
The Incas utilized the nature and geographic location such as earthquakes to adjust and
strengthen temples, collected rainwater from Machu Picchu and used the hidroalica
energy created, took advantage of the different altitudes of the terraces and wind to
regulate temperatures so they could have different cultivations, and used volcanic rock
of Machu Picchu as construction material.
2.1.2
Life Cycle Inventory
In general the material most used for their constructions was wood, silver, bronze, sand
and the volcanic rocks extrusive or intrusive. Intrusive were from the magma or lava
that cooled at great depths within the earth, and that millions years later emerged. Softer
stones were used in Inca walls and used to be Calizas. Among other rocks utilized there
are the Cuarcitas, rocks formed mostly of metamorphic sandstones, Basalto, very
popular and abundant among extrusive rocks, Andesitas, which are abundant in the
region having excellent quality and are preferred in the Inca arquitecture, and Granite,
used in a broader sense, these are intrusive igneous rocks and have a equigranular
texture (fine grain and uniform) that differ from extrusive. There exist many myths in
how the Incas cut the rocks but it is known that in order to separate the fissures of the
rocks they helped themselves with brass levers that could be a meter or longer. It is also
known that they would fracture the rocks filling the holes with water, which when
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frozen overnight made rocks detach. In order to transport these rocks, first they worked
the surface on
Figure 2. Surface to transport large blocks
which they will displace large blocks since small blocks were loaded in their backs.
Once the floor was very softened inclined planes were built as shown in the image.
They also used some auxiliary elements such as rounded stones or boulders, and rollers
as wheels.
2.1.3
Life Cycle Impact Assessment
Most of the tools used by the Incas to construct their city were very Earth friendly that
is why they do not have a high impact in the environment. Only one impact to the
environment can be cutting trees to obtain wood for tools or whenever it was needed.
2.1.4
Interpretation
In conclusion, it can be stated that the Machu Picchu city had a high level of
sustainability since the Incas used some of the 12 Principles of Green Engineering for
their constructions, and since almost most of the infrastructure does not have a high
impact in the environment. The city was complete and very consistent.
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Figure 3. The Guardian House
3. The Guardian House
The Guardian House is a place built at the highest point in the city of Machu Picchu,
but in order to accomplish its purpose Incas used 3 of the 12 principles of Green
Engineering to build this place. Below are the 3 principles used by the Incas and how
they are applied in The Guardian House;
-4th Principle: By building a house for the guardians where they had a view for the
whole city, the Incas eliminated the need of guardians in the city as well as guardians
stations in the city, in other words they minimized the energy of guardians walking
through the city as well as the number of guardians.
-6th Principle: This principle was applied by building The Guardian House at the highest
point in the city, (mountain), rather than build a tower in order to get a view of the
whole city.
7th Principle: The Guardian House’s roof was made out of lianas and their life cycle was
estimated to be around two years because of the big storm the city had due to the event
of El Nino. This life cycle was enough to let the lianas grow again and be ready for their
used in the next two years.
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3.1 Life Cycle Assesment
3.1.1 Goal and Purpose
The Purpose of The guardian House was to control the entrance from the Inca trail to
Machu Picchu as well as supervise all agricultural and urban area.
3.1.2
Life Cycle Inventory
When analyzing the construction for The Guardian House we can observe the different
materials the Incas used in it construction method, along the materials they used we can
identify the use of volcanic rocks, lianas and logs for the roof. Something that would
count as part of the inventory for The Guardian House would be the whistle the
guardians used to notify the city of any abnormality that could happen.
3.1.3
Life Cycle Impact Assessment
The impact caused by the construction of The Guardian House was minimal since the
Incas did not use any type of construction method that contributed with a foot print that
could affect the environment. The methods the Incas used are not very clear yet, the
only foot print that could be caused by the Incas could have been the burning wood for
their meal and the waste of it.
3.1.4
Interpretation
The Guardian House was a place where guardians had a strategic location by taking
advantage of the mountain’s slope and locating the house at the end of the Inka trail and
the entrance of Machu Picchu allowed them to get a control of the whole city and the
people coming from the Inka trail.
4. The Kallanka
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The Kallankas were big rooms constructed for different uses.
Principle 1 Inherent rather than circunstancial. The Kallankas were designed with a lot of
windows to be able to use the solar energy to have light insight those big rooms. Also, the wind
that passed through the windows helped to keep the rooms fresh.
Principle 3 Design for separation. The roofs in the Kallankas were made from organic
materials such as thatch from the local wild grass held by wooden beams and strips of llama
skin. Therefore, the separation and recycling of the different components for these type of roofs
did not require a lot of processes.
Principle 4 Maximize mass, energy, space, and time. Maximizing the efficiency of the
Kallankas was included in the design since they were used for different purposes and to serve a
lot of people in the same space and at the same time.
Principle 6 Conserve complexity. The complexity of the construction, how the stones were
worked to perfectly fit one with other, allows the Kallankas to be used for a long period of time
and the prove is that the buildings are still there.
Principle 9 Minimize material diversity. The materials used in the construction of the Kallankas
are the same used through the whole Machu Picchu construction. The materials are cantera
stones for the walls, sea sand for the floors, and the wild grass and wooden beams for the roofs.
Principle 10 Integrate local material and energy. Most of the materials used in the construction
of the Kallankas were extracted from the local area. The only material extracted from outside
the area was the sea sand.
Principle 11 Design for commmercial “afterlife”.The stones used in the Kallankas construction
still can be used as foundation of new houses or something else since the hardness of the stones
is about 6 on the Mohs scale.
Principle 12 Renewable rather than depleting. The roofs of the Kallankas were made from
renewable resources. Biological materials like thatch are often cited as renewable.
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4.1 Life Cycle Assesment
4.1.1
Goal and Purpose
The Kallankas were public buildings with different uses. They were used to host a lot of people,
as high schools, and/or warehouses.
4.1.2 Life Cycle Inventory
The materials used were cantera stones for the walls, sea sand for the floors, and thatch roofs
held by wooden beams and llama skin.
4.1.3
Life Cycle Impact Assessment
The Kallankas construction had probably a minimal impact since the Incas worried in keeping
the equilibrium with the earth. The impact could be at leveling the ground and bringing sand
from the sea to make the floors. Also, the constant roof replacement could had affected the
growing of the wild grass to get the thatch.
4.1.4
Interpretation
Due to a lot of raining in the area, the Incas developed a great drainage system to avoid
flooding. The constant roof replacement was solved by making the inclination of the roofs
steeper, often 60 degrees. The roofs used to be changed every 4 or 5 years.
5. Perspectives from the Different Engineering Disciplines
5.1 Industrial Engineering
From an Industrial Engineering Perspective, some of the key points that could be
observed during the visit and after what we were told by the guide are the organization
of workers for the construction of Machu Picchu, elongation of job shifts during the
day, extreme utilization of agriculture and animal husbandry, and utilization of tools to
accelerate the processes of construction and agriculture. Not forgetting that the Incas
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optimize their constructions thinking in every little detail to avoid problems that they
could face in the future such as the seismic zone, the phenomenon of “El Nino” which
could cause flooding, and drainage.
5.2 Civil Engineering
From a Civil Engineering perspective, the most innovated and sustainable technique the
Incas applied in Machu Picchu was the hydraulic or draining system, building in a
permeable floor that allowed them to survive floods caused by the “El Nino” event. One
of the reasons this method is very important was because before of building a whole city
the Incas had to first think about how to supply this new city with water for their people
and the agricultural use, if they were located surrounded by mountains. After creating
this water system, the Incas started to build, and the optimized every space of the
mountain the build on it, creating agricultural areas, houses for the community, and
temples for their religion beliefs, creating a city without the need to go out to look for
food or water, they build an autonomous city.
5.3 Mechanical Engineering
From a mechanical engineering perspective, the main mechanism observed during the
visit is the way they moved those giant stones from one place to the other for the
construction of Machu Picchu. The system consisted in stone rollers tight to the giant
stones by rope and pushed by many men. Also, how they worked the stones to make
them fit perfectly and without using any type of cement or anything else to putting them
together.
6. Conclusion
In this report it can be observe how the Incas applied the 12 principles of Green
Engineering before of all this technology era we are living in now, and this may take in
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to consideration all the projects that are being realized and how many of them are
applying these same 12 principles the Incas applied in their society. Now days it seems
that the economy and time rules all the planning systems, but without taking them in to
consideration the 12 principles can be applied and reduce the damage that these projects
are causing to the earth.
References
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7, 2015, from http://www.acs.org/content/acs/en/greenchemistry/what-is-green
chemistry/principles/12-principles-of-green-engineering.html
Anastas, P., & Zimmerman, J. (n.d.). Through the 12 Principles GREEN Engineering.
Retrieved June 7, 2015, from http://www.lucs.lu.se/wp
content/uploads/2015/02/KKEG15_LittSem1_principles-of-green
engineering.pdf
Jarus, B. (2012, August 31). Machu Picchu: Facts & History. Retrieved June 9, 2015,
from http://www.livescience.com/22869-machu-picchu.html
MACHU PICCHU (IV): PLANIFICACIÓN y CONSTRUCCIÓN DE LA CIUDAD/
City planning and development. (2013, November 8). Retrieved June 8, 2015,
from https://formentinatura.wordpress.com/2013/11/08/machu-picchu-iv
planificacion-y-construccion-de-la-ciudad-city-planning-and-development/
Turismo Universal. (n.d.). Retrieved June 8, 2015, from
http://turismouniversal.com/arquitectura-inca-materiales-y-tecnicas
construccion-y-estilos.html
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