INTRODUCTION
Years ago, the lives of humans have been connected to the environment. Later the rapid growth
of urban population has led to numerous challenges, including overcrowding, open space
reduction, and increased energy consumption.
“We can’t build up why not build down”
“The underground has enormous potential for realizing spatial benefits.” Sir Norman Foster
Subterranean architecture, which involves building structures beneath the ground level, has
emerged as a potential solution to these challenges.
AIM
To achieve the goal of subterranean architecture to provide solution for urban density
OBJECTIVES
• To maintain the existing natural land of the area by the whole.
• Understanding the subterranean spaces and its functions.
• The usage of land efficiently by utilizing the subterranean space.
• Understanding the construction techniques of subterranean architecture
• Disaster management
SCOPE
This research help to achieve the urban needs of future without destroying open quality land
and helps in maintaining relationship with buildings and surroundings
LIMITATION
This research study is limited to understanding subterranean architecture and
Its application on urban density
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SUBTERRANEAN ARCHITECTURE
METHODOLOGY
HISTORY OF
LITERATURE STUDY
CASESTUDY
SUBTERRANEAN
ARCHITECTURE
EXAMPLES
DATA COLLECTION
WHAT IS
ABOUT PROBLEM
SUBTERRANEAN
ARCHITECTURE
INFERENCE
TYPOLOGY
ISSUES IN INDIA
NEEDS AND
CHALLANGES
INFERENCE
HUMAN PRECEPTION INFERENCE
CONCLUTION
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SUBTERRANEAN ARCHITECTURE
LITERATURE STUDY
Data collection
What is subterranean architecture?
Subterranean
under earth surface
Subterranean architecture is building partially or fully under the earth surface. It is not a new
concept, since the beginning of humankind this concept is used in finding shelters underground
by creating caves, refuges, tunnels as an answer for most primitive needs.
ABOUT PROBLEM
In the globalization era, the most important obstacles which mankind is faced with are climate
change, energy resources shortage and population increase
The promise of jobs and prosperity, among other factors, pulls people to cities. Half of the
global population already lives in cities, and by 2050 two-thirds of the world's people are
expected to live in urban areas. But in cities two of the most pressing problems facing the world
today also come together: poverty and environmental degradation.
The UN estimates that 55% of the global population lives in urban areas – a figure that is
projected to rise to 68% by 2050. With few exceptions, cities are expected to become bigger
and more numerous.
Poor air and water quality, insufficient water availability, waste-disposal problems, and high
energy consumption are exacerbated by the increasing population density and demands of
urban environments.
Because of land scarcity in urban areas people started to build every inch of land this unplanned
urban growth leads to a concrete jungle with no open space which affect quality of life, nature
elements, health, restricts interaction and other productive activities.
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SUBTERRANEAN ARCHITECTURE
TYPES OF SUBTERRANEAN ARCHITECTURE
Figure 2
Example of submerged structure
Figure 2.1
Example of partially submerged structure
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SUBTERRANEAN ARCHITECTURE
Figure 2 .2
Example of earth covered structure
TERRA CENTER ELEMENTRY SCHOOL
Figure 2 .4
INFERENCE






Rather then completely submerged structures ,submerged and partially
submerged structure has advandage of creating a connection with above ground
and subterranean surface
Natural Lighting and ventilation can be easily achived by using submered and
partially submerged
figure 2.5
In Submerged structures ground plane and resourece over it can be partially
saved
In completely submerged structure ground plane and resource are not get
distrubed

figure 2.6
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SUBTERRANEAN ARCHITECTURE
HISTORY OF SUBTERRANEAN ARCHITECTURE
The earliest inhabitants of underground space were troglodytes or cave-dwellers. Human’s first
few architectural endeavours were artificially created caves. Many historians have researched
further to understand the evolution of the underground dwelling system.
Humans and animals alike have used seeking shelter within the earth to take advantage of the
protective and insulative characteristics of the soil long before recorded history. Subterranean
dwellings were simple yet sophisticated, a means of dealing with harsh climates, and helped to
create a hostile environment. Subterranean dwellings offered refuge from arid deserts to polar
cold regions, from exposure to the sun, wind, storms, and severe changes in atmospheric
temperatures, as well as providing thermal protection during seasonal temperature changes.
There are many historical examples of people living underground. Such settlements were
usually found in places with extreme heat or cold. In some cases these cities mainly served as
spaces for defence purposes. Most of these cities contain spaces found in other cities such as
religious spaces, spaces for communal gatherings, bedrooms, kitchens, bathrooms, spaces for
animals, water tanks, storage areas, tombs etc. But they also contain certain spaces which are
very specific to them such as ventilation shafts and connecting tunnels.
Derinkuyu - turkey
Derinkuyu is located in Cappadocia, Turkey along with 40 other underground sites.
Derinkuyu could accommodate around 20,000 people and was continuously occupied from the
8th century BCE to as late as 1923. Derinkuyu went down to a depth of 60ms underground and
it contains oil presses, cellars, stables, chapels and store rooms.
Figure 2 .7
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SUBTERRANEAN ARCHITECTURE
Figure 2 .8
Figure 2 .9
Its spatial range is incredible he had a capacity for up to 20 thousand inhabitants. The entire
underground system has up to 18 floors while the depth of the deepest floor.
The city has only one main entrance which is also protected by a large circular stone with
retractable system. It means that his defence has been very effective because defending a
narrow hole was relatively well realized. Openings having larger area would be substantially
less protected. If we think about the development of architecture in the future so it is evident,
the demographics in the future will increase the need for building underground cities that will
become part of the city lying on the surface. This is already the current state because most of
the world's cities have an extensive system of underground structures. Requirements in time
will increase further. This presents greater demands infrastructural, environmental, capacitive,
and more. It will use a series of underground technology in underground cities, and many of
them will become more urbanized. Utilization of underground space is still a hot topic because
of the increasing occupation of the surface areas.
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SUBTERRANEAN ARCHITECTURE
Figure 2 .10
The character of buildings in derinkuyu underground city
In the underground city there is a huge amount of different objects.
According to both their size and depending on the purpose. In terms of size there is quite tiny
caverns in which they were placed the tomb. While there is a huge cavern where it was school
or a religious place of social gathering rooms, bedrooms, kitchens, bathrooms, stables for
animals, water tanks, caverns collecting for water wells, food storage, wine, separate tombs
and burial place, weapons depot
1st floor
stables for horse and cattle
Lead to prayer rooms and schools
lead to granaries and wineries
But there are also quite specific objects that we do not find in cities built on the surface. That's
objects are ventilation shafts, connecting tunnels etc. It is obvious that Derinkuyu is among the
largest underground cities in the world. It also represents the greatest concentration of
underground cities in the world. The individual floors were mutually interconnected opening
doors. Stone circular door can be opened only from the inside for security reasons.
Underground spaces in Cappadocia also dealt
The most important system of the town existence is to create a self-propelled air conditioning.
There were discovered more than 50 ventilation shafts. They were designed to allow air to
circulate by itself. The whole system was designed so that all of the lowest and the most remote
parts are sufficiently ventilated to ensure the necessities of life
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SUBTERRANEAN ARCHITECTURE
Shows the doors of the city as well as the hole in the door to help open it.
Figure 2 .11,2.12
Matmata city - tunisia
Matmata city in the southern part of Tunisia with the dry and low land where
thousands of people lived in those caves connected to side houses by the courtyard (see figure
2), which is between 20-40 feet deep. Where every hole was considered a neighborhood that
fits hundreds of people to make the courtyard a social communicating center. For the
accessibility and travel to other parts, it happens from above by diagonal outlay that connects
between the yards and the houses for these houses to have full isolation of high temperatures
and fast wind.
Figure 2 .13
shows the horizontal projection of the city of Matmata- Tunis
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SUBTERRANEAN ARCHITECTURE
INFERNCE
ANALYSIS
Derinkuyu
underground
city
Construction
Curved out of
Technique
soft volcanic
& Materials
rock
Typology
Mixed use
Purpose of going Protection
subterranean
From harsh
climate and
enemies
People
20000 peoples
occupancy
lived there
Depth
Internal
connectivity
activities
ventilation
Current
situation
Matmata city
Rock cut
Sunken
structures
residence
Protection
From harsh
climate
Exact data
unknown 1000’s
of people lived
there
6 to 9 m
Internal rooms
where connected
With tunnels
Residential
activities
85m
Cities where
connected
through tunnels
 Tending
cattle
 Running
wineries
 Making
dairy
products
 Flour mills
 Oil
pressing
 Residential
activities
Through shaft
Through
courtyard
Archaeological
Some people still
tourist
Lives in there &
attractions
also act as
tourist spot
INFERENCE
1. BOTH CITY
WHERE
CONSTRUCTED
BY CURVING
ROCK WHICH
PROVIDE
NATURAL
STRUCTURAL
STRENGTH
2. THE REASON
FOR THE
SUBTERRANEA
N
ARCHITECTUR
E IS
PROTECTION
FROM
CLIMATE AND
ENEMIES
3. BOTH CITIES
USE TUNNELS
FOR
CONNECTING
OTHER AREAS
OF
SUBTERRANEA
N
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REASON FOR MOVING TOWARDS SUBTERRANEAN ARCHITECTURE
Then
Condition of safety
In past people create underground cities to hide from raid horses and infantry
armies and to protect from harsh climate and winds
URBANIZATION OF INDIA
Figure 2 .14

Most Urbanized States: Tamil Nadu 43.9%; Maharashtra 42.4%; Gujarat 37.4%

3 out of world's 21 mega cities: Mumbai (19 million), Delhi (15 million), Kolkata (14
million)

23 Large cities in 1991 and 40 in 2001
ISSUES IN INDIA DUE TO URBAN DENSITY
Overcrowdings
overcrowding is situation in which too many people live in too little space. Overcrowding is a
consequence of over population in urban areas, Due to this open space get reduced.
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This is well exhibited in almost all big cities of India for example Mumbai has one-sixth of an
acre open space per thousand populations though four acre is suggested standard by the Master
Plan of Greater Mumbai.
In Kolkata a report by NGO suggest that the open space is shrunk to 5% from 13 % a decade
ago due to an impact of infrastructure boom encroachment of parks and feeling of tress
happened. According to WHO, at least 15 % of a cities total area should be open space
Figure 2 .15
Figure 2 .16
Chennai flood is the direct example caused by urban density.
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Traffic
In traffic, there is an overcrowding of a route, leading to slow and inefficient flow which makes
movement difficult. Large increases in motor vehicle usage have resulted in congestion on the
roads. Congestion within urban areas restricts accessibility. Traffic flow could be controlled by
various rules, regulation and signs which are used to keep traffic flow smoothly. The traffic
flows helps to avoid collisions and other hazard.
Biodiversity Threatened
City growth destroys natural areas flowing with new and endangered animal and plant life.
No matter how small, each species plays an important role in how the Earth works. Without
this variation in life, humans suffer. Biodiversity protects water and soil from contamination,
stores and recycles nutrients, breaks down and absorbs pollutants and helps areas to recover
faster from disasters. Biodiversity also provides people with medicine, food and air.
Urbanization limits our access to these resources.
Problem of air Pollution
Suspended particulates in the air come from motor vehicle fuel combustion. Soot, dust, lead
and smoke make up the particulates. They pose a serious threat to health. Lead alone can
cause brain damage, learning disabilities and premature death in children. The World Health
Organization stated suspended particulate concentration should add up to less than 90
micrograms per cubic meter. The suspended particulate concentration soars over that
measurement in cities with a population of 8 million or more.
Reason for moving towards subterranean architecture
Now

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Reduced occupancy space on surface
Can reduce the energy demand for thermal comfort
Increase in noise pollution in cities
To reduce dust loads
To provide Quality open space required in urban space
To preserve land resources
Provide shelter against attacks and natural disasters
GOVRENMENT SCHEMES ON SOLVING URBAN DENSITY ISSUES IN INDIA
SMART CITY MISSION
Launched on June 25, 2015, the Smart Cities Mission is a flagship scheme under the Ministry
of Housing and Urban Affairs. This ambitious programme by the Indian Government aims at
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building 100 Smart Cities across India with focus on planned urbanisation and sustainable
development as a support system for the neighbouring cities. It also involves the development
of high-quality infrastructure with provision of basic amenities, education, health services, IT
accessibility, digitisation, e-governance, sustainable development, safety and security. Global
cities such as Singapore, Japan, and the USA are offering valuable support to India’s mission,
which also emphasises on economic development of urban centres by creating more jobs and
enhancement in income.
AMRUT (Atal Mission for Rejuvenation and Urban Transformation)
Launched in 2015, the focus of the AMRUT scheme was on infrastructure creation that has a
direct link to provision of better services to the citizens. Closely connected to the Swachh
Bharat Mission, the scheme includes provision of water supply facilities, sewerage networks,
storm water drains, urban transport, and open and green spaces, across the selected 500 Indian
cities. The allocated budget under the scheme is around Rs 50,000 crore for the period 2016 2021.
National Urban Transport Policy
The National Urban Transport Policy involves incorporating urban transportation as an
important parameter at the urban planning stage. It also focuses on the introduction of
intelligent transport systems, reduction of pollution levels and encouraging greater use of
public transport and no motorized modes through central financial assistance.
NEED FOR SUBTERRANEAN ARCHITECTURE IN INDIA
India is a developing country with 53 cities has population over million. Major cities like
Mumbai, Kolkata, and Chennai are suffering with problem caused by urban density
Overcrowding leads to reduction in open space , destroy resource, agriculture lands cover drain
paths other issues like traffic congestion and air pollution are the major problem in urban space
As in India subterranean has great potential to solve the issues in urban area due to urban
density. By going subterranean the above ground open space can be conserved, by using
subterranean tunnels for transportation helps in reducing congestion and air pollution in urban
space can be reduced
CHALLENGES OF PLANNING SUBTERRANEAN SPACE IN INDIA
The world population is getting concentrated in the urban settlement. It is important to make
provisions for adequate Physical and Social Infrastructure in the cities. Issues of land
acquisitions, need for compact cities, Urban Sprawl etc. had increased the intensity &
complexity of the infrastructure provision in Indian cities. The traditional surface planning and
zoning approach of land utilization would no longer be a solution to all these complexities since
land is a limited a resource. Sub-surface is not looked as a resource but a last agenda to urban
planners. The effective utilization of both surface and subsurface spaces can solve the problem
of Urban Built Environment and make cities sustainable in terms of land utilization. In India
context, unplanned use of Urban Underground Spaces had raised major issues in urban
Infrastructure. In the near future this subsurface space will be a crucial indicator for sustainable
planning of Indian cities.
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Lack of skilled worker -In India very few institutes like Central Institute of Mining and Fuel
Research, Indian School of Mines etc. conduct training programs related to mining and related
aspects. It is important to establish specialized institutes which would focus on R & D and act
as training to generate skilled manpower in the field of underground construction.
General Public Perception of Subterranean Space
Wada and Sakugawa (1990) have carried out a survey to get the response on various types of
anxiety of underground workers while working underground. The result of their survey in
response to a question, ‘How often do you feel anxiety at working underground?
Figure 2 .18
The greatest anxiety relates to the feeling of being isolated from the outside world. This type
of anxiety is especially high among office and subway station workers. In comparing responses
of people who worked in shallow subway station vs those who worked in a deep station, the
extent of anxiety was not found to be very different. However, among people working at the
deep station, the anxieties about physical health and isolation were relatively higher than
among those who worked at the shallower station. However, it is believed that the potentially
negative psychological and physiological reactions can be diminished or alleviated to a great
extent by utilizing proper design techniques.
Pros of subterranean architecture
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In regions susceptible to extreme weather, subterranean architecture is safer and more
reliable than conventional, flat-surface architecture.
Subterranean architecture can be constructed in places that traditional architecture
merely cannot, like on steep surfaces.
Subterranean properties merge easily into their natural surroundings, making them an
excellent way for conservation areas.
Earth is a great natural insulator, maintaining the warm temperature during winter and
cool during the summer, therefore diminishing the energy consumption of a
subterranean dwelling. Use of subterranean architecture cost 80-95% less than a
traditional house to heat and cool.
Subterranean architecture the use of earth helps with the natural soundproofing of the
structure and helps to maintain privacy from the outside.
Subterranean architecture is more likely earthquake resistant.
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Cons of subterranean architecture
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construction is expensive
The unconventional nature of subterranean or underground architecture requires many
planning experts and requires cautious consultation during the construction process.
Subterranean construction needs significant care taken during and after the construction
of the structure, as to moisture and might increase costs.
The psychological shift required for moving to a subterranean residence can sometimes
be uncomfortable.
Guaranteeing excellent ventilation and lighting can be a little difficult to achieve in
subterranean architecture. Complex ventilation methods may require an expert’s
involvement.
Case study
PALIKA BAZAR – CONNAUGHT CIRCLE, NEW DELHI
Introduction
Connaught Place is one of the largest financial, commercial and business centres in New Delhi,
India. It is often abbreviated as CP and houses the headquarters of several noted Indian firms.
As of July 2018, Connaught Place was the ninth most expensive office location in the world
with an annual rent of US$153 per sq. ft. The main commercial area of the new city, New
Delhi, occupies a place of pride in the city and are counted among the top heritage structures
in New Delhi. It was developed as a showpiece of Lutyens' Delhi with a prominent Central
Business District (Delhi). Named after Prince Arthur, 1st Duke of Connaught and Strathearn,
construction work began in 1929 and was completed in 1933. A metro railway station built
under it is named Rajiv Chowk (after Rajiv Gandhi) Connaught Place's central park has long
been a venue for cultural events and is a popular hangout for locals. In 2005–06, it was rebuilt
after the construction of the Delhi Metro station below it. That station, Rajiv Chowk, is the
interchange for the Yellow and Blue lines of the Metro and one of the largest and busiest
stations in the network. Connaught Place hosts various cultural events in the central park area
such as the Urdu Heritage Festival, One Billion Rising demonstrations, Delhi Government's
Youth Festival, Awam Ki Awaz (Voices of People) concert and many other
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figure 3
LOCATI ON- CONNAUGHT CIRCLE, NEWDELH
figure 3.1
figure 3.2
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ALIGNMENT- starting from the
inner circle (Rajiv chowk), extended
till the outer circle (Connaught circle)
Figure 3.3
ROAD GEOMETRICS- parallel
roads connecting inner circle (Rajiv
chowk) and outer circle (Connaught
circle) • radial road no.2 opening to
palika parking exit, • radial road no.1
opening to entry and exit no 5,6,7 of
palika bazar • service road opening to
palika parking entry and gate no. 2,3,4
of palika bazar
Figure 3.4
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Figure 3.5
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MAJOR ACCESS TO THE SITE
• parallel roads connecting inner circle (Rajiv chowk) and outer circle (Connaught circle) •
radial road no.2 opening to palika parking exit, • radial road no.1 opening to entry and exit no
5,6,7 of palika bazar • service road opening to palika parking entry and gate no. 2,3,4 of palika
bazar
MAJOR ACCESS INTO THE MARKET
Gate no. 1: Main gate. Faces Connaught Place Central Park, with F Block on the right and
Palika Underground Parking on the left. Staircase entry
Figure 3.6
Gate no. 2: Faces Palika Underground Parking. Handicap ramp entry.
Figure 3.7
Gate no. 4: Spiral staircase entry with two doors, one not in use. Door in use faces Parliament
Street, Regal Building and Jeevan Bharti building
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Gate no. 5: Spiral staircase entry with two doors. One door faces Jan path, N Block and Jeevan
Bharti building, the other faces towards Palika Underground Parking
Gate no. 6: Staircase entry. Faces N Block and F Block
Figure 3.7
Gate no. 7: Handicap ramp entry. Faces F Block
Figure 3.8
Utilities There are few utility areas like a waiting hall A STAGE and a paid water atm
Figure 3.9,3.10,3.11
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Water supply
1.25 lakh liters of water storage tank from Delhi jal board
Electricity,
Connected to the electricity board. Runs completely on electricity
Figure 3.12
Telephone,
Bsnl connections. Only if necessary for them.
Sanitary,
4 toilet blocks
Figure 3.13,3.14
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Fire,
Firefighting systems available with separate water tank, 1 lakh litre capacity with sprinkler
system and separate fire extinguisher
Figure 3.15,3.16,3.17
Storm water drainage,
No choice of storm water entering the building. It is completely sealed
Waste disposal
• The waste water is stored into two sump wells and later pump them out to main sever lines
to stop back flow.
• The sump inside is for grey water
• The sump outside is for black water
• Garbage is disposed into common drums of 200 litres each. And unloaded outside twice a
day. There are no garbage separations.
Figure 3.18,3.19,3.20
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Lighting
(Natural and Artificial)
Tube lights, fluorescent lights and domes for natural lighting
Figure 3.21
HVAC
Completely air conditioned with three ac plants. There is no other opening for air to enter.
Figure 3.22
Elevators / Escalators There are escalators only on the main entrance of palika bazar
Figure 3.23
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Landscape features
The market has a park on its roof. And similar park and a gathering area with a stage above
the parking
Figure 3.24,3.25,3.26
Sustainable aspects,
No sustainable aspects. No rainwater harvesting etc.
People usage,
2000 people per hour
2000 permanent throughout the day.
26000 people in 12 hours on an average for a day.
Construction type,
Rcc walls, gypsum false ceilings, masonry partition walls for shops and offices
Figure 3.27
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Water proofing,
7 layers of bitumen plastering. APP membrane (Atactic Polypropylene Membrane) sheets to
be introduced in the recent times for future water proofing.
Flooring,
The entrance and the stairs are of brown granite finishing,
The ramps are textured tiles
The flooring is with fancy tiles
The toilets too are floored with fancy tiles
The pavements are treated with granites and kerb walls.
Figure 3.28,3.29,3.30
PROS


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Act as a urban oasis
Multi-functional space
Reduce environment impact
CONS

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Insufficient width of pedestrian walkway
Insignificant/ compromised entries that look hidden in terms of street picture
Green terrace above Palika shopping complex lies unused and inactive for major part
of the year, due to absence of seating, shading mechanism and lack of planned
activities
Discontinuous pedestrian circulation at Plaza level
Insufficient lighting
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THE PATH
LOCATION – TORONTO, ONTARIO, CANADA
MANAGEMENT-CITY OF TORONTO GOVRENMENT
NO.OF.STORES- 1200
PARKING – 20 parking garages
PATH is downtown Toronto's underground walkway linking 30 kilometres of shopping,
services and entertainment. Follow PATH and you'll reach your downtown destination easily
in weatherproof comfort.
Figure 3.31
HISTORY OF PATH

The first underground path in Toronto originated in 1900 when the T Eaton Co. joined its
main store at 178 Yonge St. and its bargain annex by tunnels. By 1917 there were five tunnels
in the downtown core. With the opening of Union Station in 1927, an underground tunnel was
built to connect it to the Royal York Hotel (now known as the Fairmont Royal York). The real
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




growth of PATH began in the 1970s when a tunnel was built to connect the RichmondAdelaide and Sheraton Centres.
In 1987, City Council adopted the recommendation that the City become the co-ordinating
agency of PATH and pay for the system-wide costs of designing a signage program.
In 1988, design firms Gottschalk, Ash International, and Keith Muller Ltd. were retained in
by the City of Toronto to apply the design concept for PATH.
PATH's name and logo are registered to the City of Toronto. The City co-ordinates and
facilitates the directional signage, maps and identity markers throughout the system.
Each segment of the walkway system is owned and controlled by the owner of the property
through which it runs. There are about 35 corporations involved.
In the early 1990s, signage for PATH was developed to provide pedestrians with better ease
of use and functionality. The signage enhances PATH's visibility and identity, ultimately
increasing its use, attracting more people to downtown Toronto, and drawing more businesses
there.
Figure 3.32
Design
PATH provides an important contribution to the economic viability of the city's downtown core,
and is also used to supplement sidewalk capacity in downtown Toronto. The system facilitates
pedestrian linkages to public transit, accommodating more than 200,000 daily commuters, and
thousands of additional tourists and residents en route to sports and cultural events. Its
underground location provides pedestrians with a safe haven from the winter cold and snow,
alongside the summer heat and humidity
Coordination and signage
In 1987, City Council adopted a unified wayfinding system throughout the network. The design
firms Gottschalk+Ash International and Muller Design Associates were hired to design and
implement the overall system in consultation with a diverse group of land owners, City staff and
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stakeholders. A colour-coded system with directional cues was deployed in the early 1990s.
Within the various buildings, pedestrians can find a PATH system map, plus cardinal directions
(P (red) for south, A (orange) for west, T (blue) for north, H (yellow) for east) on ceiling signs at
selected junctions. The signage can be hard to find inside some of the various connected buildings.
Building owners concerned about losing customers to neighbouring buildings insisted that the
signs not dominate their buildings, or their own signage system. The city relented and the result
is the current system. Many complain that the system is hard to navigate
Figure 3.33,3.34,3.35,3.36
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Figure 3.37
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CONNECTED FACILITIES
More than 50 buildings or office towers are connected through the PATH system. It comprises
twenty parking garages, five subway stations (Osgoode station connects only to the Four Seasons
Centre), two major department stores, two major shopping centres, six major hotels, and a railway
terminal. The CN Tower, Ripley's Aquarium of Canada, and Rogers Centre are connected via an
enclosed elevated walkway, called the Skywalk, from Union Station, although the walkway does
not have indoor connections to these attractions
VENTILATION AND LIGHTING
Artificial ventilation and lighting throughout the path
Someplace atrium
ABOUT PATH

According to Guinness World Records, PATH is the largest underground shopping complex
with 30 km (19 miles) of shopping arcades. It has 371,600 square metres (4 million square
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






feet) of retail space. In fact, the retail space connected to PATH rivals the West Edmonton
Mall in size.
The approximate 1,200 shops and services, such as photocopy shops and shoe repairs, found
in PATH, employ about 5,000 people. Once a year, businesses in PATH host the world's
largest underground sidewalk sale.
More than 50 buildings/office towers are connected through PATH. Twenty parking garages,
six subway stations, two major department stores, eight major hotels, and a railway terminal
are also accessible through PATH. It also provides links to some of Toronto's major tourist
and entertainment attractions such as: the Hockey Hall of Fame, Roy Thomson Hall, The Air
Canada Centre, Rogers Centre, and the CN Tower. City Hall and Metro Hall are also
connected through PATH.
There are more than 125 grade level access points and 60 decision points where a pedestrian
has to decide between turning left or right, or continuing straight on. The average size of a
connecting link is 20 metres (66 feet) long by 6 metres (20 feet) wide.
The building furthest north on the PATH network is College Park at College and Yonge
Streets. The building furthest south that can be accessed through PATH is the Toronto
Convention Centre's Convention South Building. PATH does not follow the grid patterns of
the streets above.
Each letter in PATH is a different colour, each representing a direction. The P is red and
represents south. The orange A directs pedestrians to the west, while the blue T directs them
to the north. The H is yellow and points to the east.
Signage includes a symbol for people with disabilities whenever there is a flight of stairs
ahead.
With 3.7 million square feet of retail space, there are 1,200 restaurants, shops and services in
the PATH, generating roughly $1.7 billion in sales annually. An estimated 4,600 jobs are
located in the PATH. The PATH generates approximately $271 million in federal, provincial,
and municipal tax revenue annually
MORE SUBTERANEAN BUIDINGS
THE CALIFORNIA ACADEMY OF SCIENCES
Designed by Renzo
Piano in partnership
with San Franciscobased
Stantec
Architecture and was
completed in 2008. The
California Academy of
Sciences is one of the
largest museums of
natural history in the
world. It also houses an
aquarium,
the
planetarium, and the
four-story rainforest, as well as being the headquarters for the academy itself.
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The California Academy of Sciences is one of the world’s most pioneering museum building
programs and sets a record as the sustainable new home for the California Academy of
Sciences.
THE TENNESSEE GOVERNOR’S MANSION
An expansion in the form of subterranean architecture on the grounds of the governor’s
mansion in Nashville, Tennessee. Designed by the firm archimania, they went for a more
contemporary subterranean approach for the expansion. Archimania was particularly chosen
for its expertise in sustainable design, the technique to save space on sprawling grounds while
conserving the existing ancient architecture.
Subterranean Conservation Hall is a glass-walled atrium under the Governor’s lawn is
positioned 25 feet below the lawn, the oval-shaped courtyard is fully glazed. This permits
natural light to infiltrate the interior with a lot of plants and trees planted in the interior. The
Conservation Hall is slightly reminiscent of the Phipps Observatory in Pittsburgh as a sunken
greenhouse
Figure 3.39
SUNLIT SUBTERRANEAN PARKS
New York’s Lowline Lab will be a prototype of the Real Lowline. The ambitious scheme to
transform the deserted Williamsburg Bridge Trolley Terminal on the Lower East Side into the
world’s very first underground park. The founders of the Lowline—Dan Barasch and James
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Ramsey, dreamed about the idea to create the underground park more than a decade ago and
as of last year, the $83 million projects were under construction.
Figure 3.39
The Lowline is a plan to use solar technology innovatively to brighten a historic trolley
terminal on the Lower East Side of New York City. The vision is to create a magnificent
underground park, offering a beautiful respite and an artistic attraction in one of the world’s
Figure 3.40
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STAEDEL MUSEUM, FRANKFURT, GERMANY
The museum houses over 2,900 paintings, 600 sculptures, 500 photographs, and around
100,000 drawings and graphic reproductions dating from the Middle Ages to the present.
SEFAR Architecture fabric diffuses natural light softly and gently through unique glass
apertures inside a new exhibition area at the Staedel Museum in Frankfurt, Germany. The
general concept and technological specification make sure this museum building is sustainable
in all respects.
These “eyes for art”
representing
the
skylights
were
specifically
developed for the
Staedel extension
and were walked on.
Daylight entering
the exhibition space
Staedel under can be
modulated, which
can
either
be
augmented using the
cohesive
LED
lighting system or
mitigated
by
shading elements constructed into the roof light.
Figure 3.41
ANALYSIS
Why going subterranean structure rather than vertical development
Living in subterranean surface where average mean temperature is almost steady and equal to
ground surface average mean yearly temperature. Thus, in such an appropriate circumstance,
climate change has less influence and energy consumption is very less than other conditions.
Underground living provides a comfortable, tranquil, weather-resistant atmosphere. There are
varieties of investigations that indicate subterranean buildings have appropriate performance
during natural and unnatural disasters. Indeed, underground places are ideal for improving the
environment and supporting the principles of Sustainable Development and at the same time,
it is a safe place in nuclear attack, earthquake, hurricane and tsunami.
In added to the above mentioned advantages the resource on the top surface of the subterranean
structures can be preserved and can be used as an open space which can be used as a breathing
space in dense urban area.
Subterranean structures has greater advantages when compare to vertical structures
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Facts related to Human Comfort in subterranean structures
The feeling of comfort or more accurately, discomfort, is based on a network of sense organs:
the eyes, ears, nose, tactile sensors, heat sensors, and brain. In general, human comfort depends
on variety of factors. Temperature, humidity, air velocity, solar radiation, illumination rate,
environmental condition, air contamination and quality, odor, noise, ventilation and also body
metabolism have direct influence on human comfort. All factors except body metabolism,
which is different person to person, need to pay enough attention during design process. Some
conditions which may occur in underground buildings and influence human comfort are as
follow:
 Human can feel uncomfortably "hot" during the summer if the relative humidity is high,
because of evaporative cooling of the body due to sweating.
 Human feel more comfortable and do not develop cracked or dry skin problems if the
winter time relative humidity is not too low.
 Depends on the thickness and compact rate of exterior soil, ventilation can reduce or
increase. Also, humidity can influence on necessary ventilation rate.
 Indoor air quality in underground buildings is more appropriate than up ground buildings
due to the fact that today’s cities air have a lot of contamination and is smog.
 Thermal comfort can be provided easily owing to the fact that soil is appropriate thermal
mass.
 Solar radiation has less influence there and can be more pleasant in the case of appropriate
design. Indeed, there isn’t direct radiation and it can be very smooth.
 Illumination rate should take more attention due to less and indirect outdoor radiation.
 Wind has fewer effects there and cannot increase air velocity rate. However, less air
velocity can cause feeling discomfort.
 Due to being underground, there is less unpleasant noise. Related buildings have natural
acoustic system.
 Indoor environmental conditions absolutely depends on design in underground building,
however, outdoor environment has appropriate potential to feel comfortable due to less
interfere in nature.
Efficiency of subterranean architecture in Indian climate
India mostly has the climate of a tropical country. India’s northern part is situated in the
temperate belt. The northern states of India have slightly higher temperatures than other same
altitude areas during the winter season. On the other hand, during the summer season due to
the sun’s position the region experiences a dry climate like that of the equatorial regions.
India has the climate of Tropical monsoon due to its peculiar position in the Asian continent
and the Indian Ocean. The Indian subcontinent has hot summers and moderately cold winters
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As we see from the above examples
Derinkuyu – turkey and Matmata they
were the historical structure build especially
to protect them from hot climate India is also
experiences hot summers, subterranean
structures are weather proof so it’s also
applicable for winder also Special care taken
for waterproof and water drain in high
rainfall region
Figure 4
Ventilation techniques for subterranean structure
Ventilation is crucial for maintaining a safe and healthy environment in subterranean structures,
such as tunnels, mines, and underground parking garages. Here are some techniques that are
Commonly used for ventilation in subterranean structures:
Forced-air ventilation: This technique involves using fans or blowers to circulate fresh air into
the subterranean structure and exhaust stale air. The fans can be placed at strategic locations
throughout the structure to ensure proper air flow.
Natural ventilation: This technique utilizes natural air currents and pressure differentials to
ventilate the subterranean structure. This can be achieved through the use of ventilation shafts
or other openings that allow air to enter and exit the structure.
Jet fans: These are small, high-velocity fans that are installed in the ceiling of the subterranean
structure. They create a circular air flow pattern that helps to distribute fresh air throughout the
space.
Positive pressure ventilation: This technique involves pressurizing the subterranean structure
with fresh air to prevent the entry of contaminated air from surrounding areas. This is
particularly useful in situations where there is a risk of airborne pollutants entering the
structure.
Smoke control ventilation: This technique is used in emergency situations where there is a
fire or smoke in the subterranean structure. It involves the use of smoke exhaust systems to
remove smoke and other harmful gases from the structure.
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SUBTERRANEAN ARCHITECTURE AND VARIOUS SECTOR BUILDINGS
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CONCLUSION
Urbanization is a rapidly growing phenomenon that has led to increasing pressure on land and
resources, resulting in the problem of overcrowding and reduction in open spaces. This has
created a need for innovative solutions to address the challenges of urban density.
Subterranean architecture, which involves the design and construction of buildings
underground, offers a viable solution to this problem.
To analyse the feasibility of subterranean architecture provided case studies of successful
subterranean structures around the world. These case studies demonstrate the versatility of
subterranean architecture, which can be used for a range of purposes, including housing,
commercial, and public spaces.
THE SCENARIO OF TORONTO BEFORE AND AFTER THE CONSTRUCTION OF
THE PATH
Before
Before the PATH system was established, Toronto was a city with a rapidly growing
population and a bustling downtown core. However, the city was facing some significant
problems related to transportation and pedestrian congestion. The streets of downtown
Toronto were often clogged with vehicles, and the sidewalks were frequently overcrowded
with pedestrians. In addition, the harsh Canadian winters made it difficult for people to move
around the city, as they were forced to navigate icy sidewalks and snow-covered streets.
After
Since the establishment of the PATH, the city of Toronto has seen some notable changes. One
of the most significant differences is the increased ease of movement throughout the
downtown core. With the PATH system in place, pedestrians are no longer restricted to narrow
sidewalks or forced to navigate through vehicle traffic. Instead, they can move quickly and
efficiently between buildings, stores, restaurants, and other destinations. Another positive
outcome of the PATH system is that it has helped to reduce traffic congestion in the city. With
more people using the underground walkways, there are fewer cars and other vehicles on the
streets. This has improved traffic flow and reduced the overall volume of traffic in the city,
making it a more pleasant place to be.
Overall, the paper argues that subterranean architecture offers a better living environment thus
boosting natural open spaces on the land above promising sustainable solution increasing
urban density, providing an opportunity to use underground spaces creatively and efficiently
to meet the needs of growing cities.
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