UG Thesis Study Documentation

TRIBAL ART CENTER AND MUSEUM AT THE NILGRIS THESIS Submitted by ABHIRAMI S 311214251002 In partial fulfilment of the Requirements for the award of the degree of

BACHELOR OF ARCHITECTURE ANNA UNIVERSITY

MARG INSTITUTE OF DESIGN AND ARCHITECTURE SWARNABHOOMI Velur Village, Cheyyur Post Kanchipuram District Tamil Nadu - 603302 April 2019

DECLARATION I declare that this Thesis titled

“TRIBAL ART CENTER AND MUSEUM AT THE NILGRIS� is the result of my work and prepared by me under the guidance of Mr Vigneswaran and that work reported herein does not form part of any other thesis of this or any other University. Due acknowledgement have been made wherever anything has been borrowed from other sources.

Date: Signature of the Candidate : Name

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Reg Number

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BONAFIDE CERTIFICATE Certified that this Thesis forming part of Course work AR6081, Thesis, X semester, B.Arch, entitled “Tribal Art Center and Museum� Submitted by Ms. Abhirami S, Reg. No 311214251002 to the Department of architecture, MARG Institute of Design and Architecture Swarnabhoomi(MIDAS), Anna University, Chennai in partial fulfilment of the requirements for the award of Bachelor Degree in Architecture is a bonafide record of work carried by him / her under my supervision. Certified further that to the best of my knowledge the work reported herein does not form part of any other thesis.

Date

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Signature of the Supervisor : Name

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Designation

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External Examiner 1

External Examiner 2

Date:

Date:

HOD

DEAN

PRINCIPAL

ACKNOWLEDGEMENT This project consumed huge amount of work, research and dedication. Still, implementation would not have been possible if we did not have a support of

many individuals and organizations. Therefore I would like to extend my sincere gratitude to all of them.

First of all I am grateful to Mr. Vigneswaran (Internal guide) and Ar. Vyom Sinha (External guide) for provision of expertise, and technical support in the implementation. Without their superior knowledge and experience, the Project would like in quality of outcomes, and thus their support has been essential.

Nevertheless, I express my gratitude toward my families and colleagues for their kind cooperation and encouragement which helped me in completion of this project.

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Table of Contents 1.AIM................................................................................................................................7 2.OBJECTIVES..................................................................................................................7 3.SCOPE...........................................................................................................................7 4. CASE STUDY.................................................................................................................8 4.1 LITERATURE CASE STUDY........................................................................................8 4.2 LIVE CASE STUDY....................................................................................................8 5.METHODOLOGIES........................................................................................................9 6.A BRIEF STUDY OF THE INDIGENOUS TRIBAL COMMUNITIES OF THE NILGRIS BIOSPHERE RESERVE......................................................................................................10 6.1 GEOGRAPHY OF TAMIL NADU...........................................................................10 6.2 KURINJI – MOUNTAINS.........................................................................................12 6.3 INDIGENOUS TRIBAL GROUP..............................................................................15 6.4 POPULATION STATSTICS.......................................................................................16 6.5 KURUMBA.............................................................................................................16 6.5.1 Jenu Kurumbas.............................................................................................17 6.5.2 Aalu Kurumbas..............................................................................................18 6.5.3 Betta Kurumbas............................................................................................18 6.5.4 Yanai..............................................................................................................18 6.5.5 Mullu Kurumbas.............................................................................................19 6.6 KOTA.....................................................................................................................19 6.7 TODA.....................................................................................................................20 6.8 IRULA.....................................................................................................................21 3

6.9 LIMITATION............................................................................................................23 7. MATERIAL STUDY........................................................................................................24 7.1 WHY SIRE WALL?..................................................................................................24 7.1.1 ADVANTAGES OF SIRE WALL........................................................................24 7.1.2 DISADVANTAGES OF SIRE WALL..................................................................25 7.2 SOIL STABILIZATION..............................................................................................25 7.3 SOIL SPECIFICATION............................................................................................25 7.4 SELECTION CRITERIA FOR NATURAL RAMMED EARTH......................................26 7.5 SELECTION CRITERIA FOR CEMENT STABILIZED RAMMED EARTH....................27 7.6 DURABILITY............................................................................................................27 7.7 RAINFALL EROSION..............................................................................................28 7.8 SHRINKAGE...........................................................................................................28 7.9 CEMENT STABILIZATION.......................................................................................29 7.10 THICKNESS OF WALL..........................................................................................29 7.11 DESIGN................................................................................................................30 7.11.1 OUTLINE........................................................................................................30 7.11.2 SITE CHARACTERISTICS................................................................................30 7.11.3 LOCAL CLIMATE..........................................................................................30 7.11.4 SITE TOPOGRAPHY......................................................................................31 7.11.5 ARCHITECTURAL PLANS..............................................................................32 8. SITE LOCATION..........................................................................................................40

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ABSTRACT Tribal Cultural Centers: Planning for Today and Tomorrow At the end of the 20th century, tribal museums were one of the fastest growing sections of the museum field, but since then little has been published on the tribal cultural center planning. The study developed a baseline about tribal cultural centers across India. This research asked: What do tribal museums look like? How are they formed? And, why are they relevant? This survey was divided into ten sections to analyze basic information, facility, planning, land, construction, collections, visitation, and design. This study discovered that the tribal cultural centers included within the research were built to tell the stories of their people to their people and others. They had a range of sizes and funding sources, but still strive to do similar things. While tribal members were not the most frequent visitors, these facilities would not exist without them. Tribes who are interested in planning cultural centers need to remember the two types of audiences that attend these facilities, and remember to think about the purpose of the facility during the planning process for creating a new cultural center.

List of Figure

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FIG 1: Map of Tamilnadu.............................................................................................10 FIG 2: Location of Western Ghats...............................................................................11 Fig 3: Map of Indigenous Communities.....................................................................14 FIG 4: Anchor for doors and windows.......................................................................33 FIG 5: Details of Window jambs..................................................................................33 FIG 6: Details of door jamb sections...........................................................................33 FIG 7: Details of door head section...........................................................................34 FIG 8 : Reinforced concrete beam roof connections.............................................34 FIG 9(a): Pneumatic rammer.....................................................................................35 FIG 9(b): Modern concrete shuttering for rammed earth.....................................35 FIG 10: Map...................................................................................................................40 FIG 11: Macro size view of site from Google Maps..................................................41 FIG 12: Site Top View....................................................................................................42 FIG 13: Site Image 1......................................................................................................43 FIG 13 - Site image 2....................................................................................................43 FIG 13 - Site image 3....................................................................................................44 FIG 13: Site image 4......................................................................................................45 Fig 14: Sun path............................................................................................................45

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1.AIM To design a space for the tribal people which would help them research and understand the cultural practices of the other tribes for the upliftment and promotion of their art forms through the vernacular style of architecture.

2.OBJECTIVES ● To study art, culture, tradition and religious beliefs of the tribal people. ● To support and promote local art culture by providing spaces for them to meet, exhibit, teach and perform. ● To provide an institution which encourages civic participation in conserving history, culture and environment. ● To create a knowledge hub for aspiring people. ● To use appropriate materials to create a sustainable environment. ● To aid directly in the communication and promotion of the rich and diverse cultures of India, with particular emphasis on the cultures of the people of the South.

3.SCOPE To meet the objectives and to treasure the rich culture of the tribal people by providing workshop spaces where the urban population gets a chance to meet the tribal population. Providing a museum that helps in funding for the upliftment of the people and it acts as a tourist attraction which creates an awareness about the indigenous tribes. This helps in preserving their art as well as add economic value.

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4. CASE STUDY 4.1 LITERATURE CASE STUDY National – Sanskriti Kala Kendra, New Delhi.

International – Jean Marie Tjibaou Cultural Center, New Caledonia.

4.2 LIVE CASE STUDY MP Tribal Museum, Bhopal.

Manav Sangrahalaya, Bhopal

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5.METHODOLOGIES

TRIBAL ART CENTER AND MUSEUM AT THE NILGRIS

DATA COLLECTION National – Sanskriti Kala Kendra, New Delhi.

LITERATURE STUDY International – Jean Marie Tjibaou Cultural Center, New Caledonia

MP Tribal Museum, Bhopal CASE STUDY Manav Sangrahalaya, Bhopal

SPECIAL STUDY

SIREWALL

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6.A BRIEF STUDY OF THE INDIGENOUS TRIBAL COMMUNITIES OF THE NILGRIS BIOSPHERE RESERVE. 6.1 GEOGRAPHY OF TAMIL NADU Covering an area of over 130,000 square kilometers, India’s southern-most state has a variety of landscapes, terrains and habitats. There are beautiful, wavelapped golden beaches and emerald green paddy fields; lush tropical forests and cool mountain ranges. There is a staggering variety of flowers, trees, birds, mammals, marine life, insects and reptiles, a nature-made counterpoint to the cultural and historical riches of the state. It is mineral-rich, with abundant reserves of lignite, quartz, bauxite, limestone, graphite and granite.

FIG 1: Map of Tamilnadu 10

Tamil Nadu’s northern-most point is Lake Pulicat, a brackish water lake or lagoon that is home to a large variety of birds. The southern extremity of the state is also India’s Land’s End, Cape Comorin, or Kanyakumari. The Mudumalai National Park, the densely forested, flora-and-fauna rich part of the Nilgiri Biosphere Reserve is at the western end, and Point Calimere, bulging out gently into the Bay of Bengal is Tamil Nadu’s eastern limit.

Tamil Nadu has a rich diversity of plants, animals, birds, insects and aquatic life, a good proportion of it native to the state. It has taken an active role in the conservation of this natural heritage, and has set up and developed active eco-tourism and management programmes.

Ancient Tamil poetry describes five geographical landscapes in Tamil country, each evoking a particular emotional state and imagery. These are Kurinji, or mountainous regions; Mullai, or forests; Marudham, the fertile croplands and plains; Neidhal, or the seashore, and Palai, the desert or wasteland. All of these exist in Tamil Nadu, and are a lovely framework to explore the natural landscape of the state.

FIG 2: Location of Western Ghats 11

6.2 KURINJI – MOUNTAINS ●

Goddess : Seyon

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People : kuravar , poruppan, verpan, cilampan, natan, koticci, Kanwar

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Trees : Vengai, Akil, Sandalwood, Bamboo

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Animals : Monkey, bear, tiger, pig

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Bird : Parrot, peacock

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Drum : Throat (Thondagam in Tamil), frenzy (Veriyaatu in Tamil)

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Instrument : Kurinji Jaffna (Yaazh)

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Flowers : Kurinji , Kanthal , Vengai

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Industry : Tuberculosis, honey, horticulture, degradation

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Water level : Brook, stream

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Food : Millet, hill, mangornery

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Trail : Sirukudi

There are several mountain and hill ranges in Tamil Nadu. Foremost among these are the Anamalais, or the Elephant Hills, that rise sharply from the plains past Coimbatore. Geologically, they are formed from metamorphic gneiss, with veins of feldspar and quartz, and a scattering of reddish porphyrite. The Anamudi Mountain, at over 2600 meters high, is the tallest point in all of South India. The Anamalais are part of the Western Ghats, the ridged edge of the Deccan Plateau, that run along India’s western flank. This is one of the most biodiverse spots in the world, the habitat for a staggering variety of flora and fauna. The Indira Gandhi Wildlife Sanctuary and National Park, Tamil Nadu’s largest wildlife sanctuary, is in the Anamalais. It is a birder’s dream come true with over 300 bird species, including the Great Pied Hornbill and the extremely 12

rare Frogmouth. Animals include tigers, leopards, elephants, Nilgiri tahr and flying squirrels.

Further north, and also part of the Western Ghats at the meeting point of 3 states - Karnataka, Kerala and Tamil Nadu - are the Nilgiris or the Blue Mountains. With at least two dozen peaks that rise above 2000 meters, they are probably best known as the home of the hill stations of Uthagamandalam (Ootacamund) and Coonoor that are popular retreats from the searing summer heat for people from all over Tamil Nadu and beyond. One of the first wildlife sanctuaries to be established in India, the Mudumalai National Park and Wildlife Sanctuary, is in the Nilgiris, and is home to several threatened and endangered species like elephants, chital, gaur, tigers and leopards. Like the Indira Gandhi Park, the Mudumalai Park is also a tiger reserve, and the government is active in protecting and conserving the habitat and lives of the tigers in these reserves.

The Western Ghats receive abundant rainfall and provide fertile ground for the coffee, tea and spice plantations that thrive on its hillsides.

In addition to the Western Ghats, Tamil Nadu also includes the tail-end of the Eastern Ghats, an irregular and broken chain of hills and mountains running along eastern India. The Eastern Ghats end, somewhat tamely, near the Vaigai River in Tamil Nadu. The Shevaroy Hills and the hill-station of Yercaud in the northern part of the state, are perhaps the best-known of the Eastern Ghat ranges in Tamil Nadu.

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Fig 3: Map of Indigenous Communities

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6.3 INDIGENOUS TRIBAL GROUP Within

Tamil Nadu there are 36 scheduled tribes, many of which can

be found within the Nilgiris Biosphere Reserve. Of those who are considered as part of the scheduled tribes in Tamil Nadu, there are six groups that are approved as Primitive Tribal Groups (PTGs), all of which can be found in the NBR: Kattunaickens , Todas.

Kotas,

Kurumbas,

Irulas,

Paniyans,

and

The characteristics of a PTG include: “a pre-agriculture level of

technology, a stagnant or declining population, extremely low literacy, and a subsistence level of economy” (P.5, Paniyans of Nilgiri District Tamil Nadu).

When defining a tribe there can be a multitude of answers. On description from the Tribal Cultural Documentation sources a definition from anthropologist T.B. Nayak that directly states – “A tribe is a social group with territorial affiliation, endogamous, with no specialization of functions, ruled by tribal officers, hereditary or otherwise, united in language or dialect… following tribal traditions, beliefs and customs illiberal of naturalization of ideas from alien sources, above all conscious of a homogeneity of ethnic and territorial integration” (p.1, Paniyans of Nilgiri District Tamil Nadu). The tribes of India play a major role in constructing the cultural heritage of India. The development of tribal population has been a major concern for the Indian government. These tribal people are located in the hilly terrains of the Nilgris, Tamilnadu and they are involved in activities like tea production. Residing in the mountain terrains, they have been striving to uphold their indigenous tradition and customs from any foreign influence. Kota, Toda,Irula and Kurumba are the four tribes that are being concentrated in this study.

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6.4 POPULATION STATSTICS Kota

- 3110

Toda

- 2978

Irula

- 1, 89,621

Kurumba - 25,048 6.5 KURUMBA Kurumba art is a unique tribal art form found in the Nilgris. The Kurumba art is an expression of its socio-religious fabric. Four colours are used traditionally: Red (“Semm manna”) and white (“Bodhi manna”) are soils, black is obtained from the bark of a tree (“Kari maran”) and green from the leaves of a plant (“Kaatavarai sedi”). A piece of cloth is used to apply the colours onto the cowdung prepared walls. Nowadays a fresh coat of plaster is given to the wall before painting begins.

This tribe is spread throughout Tamil Nadu and within the Nilgiris there are seven distinct groups, each with their own unique features. They are known, even by the other surrounding tribes, for their skilled abilities in the forest, such as with honey hunting. This is one of the few groups that is daring enough to scale large cliffs in order to collect honey from the massive hives of Apis dorsata. They are regarded as the “honey cutting lords of the woods” (Jenu Koyyo Shola Nayakars) because of this expertise.

As is seen among other Nilgiri tribes, the Kurumbas

have an art and

musical culture. Traditionally it is the men who practice the arts (also are more likely the priests or temple caretakers) while the women are more involved with decorating the home. Some of the common instruments 16

among the Kurumbas are the bamboo pipes (bugiri and Kuvalu), 2 faced drums (are), and 1 faced drum (tambatte). There are two kinds of dances, one called the gandesa attam that is performed by the men while the other is called the yen attam is performed by the women.

Within the Nilgiris , the Kurumbas have a close connection with the Badaga community, such as with ethno-medicine and even providing music at a variety of Badaga festivals. They are an adivasi group that is somewhat specialized in foraging patterns, given that they are more focused on medicinal plants and honey. Historically they are known for their sorcery powers and ability of finding medicine in the forest. With regards to honey, they harvest all the different varieties and the honey collected from Apis florea and Dammer bees is not sold. Rather, it is kept for medicinal and food purposes, especially for pregnant women and children. They are hunter-gatherers as well as jungle dwellers found within the lower region / forested belt of the Nilgiris, specifically in

Gudular, Kotagiri, and Kil-Kotagiri.

6.5.1 Jenu Kurumbas This Kurumba division is found in the northern region of the reserve, concentrated in Mysore and Kodagu districts, and they have jenu in the name because the word means honey, for which they are skilled in collecting. In some cases they own land and cultivate land but mostly do seasonal wage labor during the seasons when they are not collecting forest produce, especially honey. The social organization of their groups is known as sangams.

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6.5.2 Aalu Kurumbas This group of Kurumbas is mostly found at the mid-range within the southern and eastern belt of the Nilgiris. They are further divided into two specific endogamous groups, being the Nagara and the Bellaga, which could be further divided into several different clans or Kulams. In their governance system they have what is called a mothali, which administers the village, along with the help of three assistants that each have a specialization (agriculture, marriage, and one as the messenger). Their villages (also known as motta or kombai) are typically constructed with bamboo, mud securing, and tiled roofs. Nowadays, more villages from this group can be found at the edge of forests, both ekking out a living from their lands and through wage labor.

6.5.3 Betta Kurumbas This group lives in the northern parts of the Nilgiri, specifically in the Gudular district. They are known for living in large settlements, which can be up to 6080 settlements. Their livelihoods are mostly dependent upon wage labor, however they are not major honey collectors. The wage labor is especially due to the rapid growth of tea cultivation in Gudular. In regards to NTFPs, they are very skilled at finding medicinal plants and herbs, and especially collect kodampuli and shikakai during the season.

6.5.4 Yanai Experts in trapping elephants and being mahouts

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6.5.5 Mullu Kurumbas This group is concentrated in the Waynaad region as well as parts of Gudular. They are best known for their abilities with hunting and bird catching, and the women are skilled at fishing. In addition, they now practice agriculture within the Wayanad vayals (fields). The traditions of animism still prevail within their religion even though much of their cultural practices of the present day are borrowed from Nayars of Kerala.

6.6 KOTA The Kota pottery included delicately conceived terracotta jewellery along with terracotta tumblers, pots, vases, tea cups, mugs, wall hangings and so on. Kota men have traditionally specialized in blacksmithing, silversmithing, roof thatching, basket making, wood-and leatherworking, and musical-instrument making.

From whom Kotagiri, one of the Nilgiri districts, was named. In total, there are seven Kota villages dispersed throughout the hills. They are best known for being the artisans of the various adivasis in the Nilgiri. Their artisan skills include being: blacksmiths, tanners, rope makers, carpenters, potters and gold and silversmiths. In addition, to bartering the artisanal goods and services as a form of livelihood they also cultivate land for various crops like grains and herbs.

Their pottery goods and tools were once especially traded with the Badaga and Toda communities before being replaced by more modern equipment, yet their artisanal goods are still desired for ritualistic purposes. It is the women of the village who shape and mold the distinct style of Kota pottery and the men 19

contribute by helping to construct the wheel and digging for the clay. The main deities for the Kota are Ainor, Amnor, and Kamtraaya (creator of the universe).

Each village will have two temples that are dedicated to the Ainor and Amnor, and their most significant festival is to commemorate Kamtraaya at the onset of their annual cycle of rituals.

6.7 TODA The Toda Embroidery, is an art work among the Toda pastoral people of Nilgiris, in Tamil Nadu, made exclusively by their women. The embroidery, which has a fine finish, appears like a woven cloth but is made with use of red and black threads with a white cotton clothbackground. Both sides of the embroidered fabric are usable and the Toda people are proud of this heritage. Both men and women adorn themselves with the embroidered cloaks and shawls.

They are one of the smaller Nilgiri tribes with a population of about 1500 that are spread throughout the Nilgiris among ~60 settlements. They are known for being nomadic pastoralists who look after their herds of semi-domesticated buffalo.

Hence, they are mostly found among the hills or upper plateaus where there are natural shola grasslands that are necessary for the buffalo to graze. With their buffalo they also practice dairying and are strictly vegetarian having mainly a diet of milk products and millets/cereals.

Grasslands are significant to the lives of the Toda however, they have had to convert some of the land for agriculture purposes, albeit cultivation is not a preferred form of livelihood. Nevertheless, the grasslands and their buffalo that roam them are held as sacred and much of the Toda rituals are related to this 20

animal and the milk it provides. They also have a practice of burning the grasslands through fire control, which is meant to help maintain a healthy ecosystem and even indirectly provides a higher yield of honey.

Collecting honey is also a major part of their livelihoods, being also part of their sacred beliefs, such as with mythology and names of rivers. They have a very distinct practice with honey collection in which they refer to their ancestral trees (handed down from father to son) as sirfs and from the cavities of these trees they collect the honey of Apis cerana. When taking the honey comb they do not use any fire or smoke, but merely blow into the cavity to calm and move the bees, and then extract the honey. Thus the brood is not destroyed in the honey collection process and insures that the colony returns every year.

Another unique feature of the Toda community is their style of dress known as Puthukulli that is made of thick cotton and with distinct patterns of the colors red, blue, and/or black. The women are also known for wearing long ringlets in their hair, which is kept in shape with the use of buffalo ghee. The villages are referred to as munds and the traditional shape of home are rounded huts that are made with different resources from the forest. Nowadays these types of homes are less common to live in, yet every village still has a sacred mund style hut for a temple and a place to store the buffalo milk. Their belief system is mostly based on the divine beings such as Tokisy, On, and Kwatene. In addition, they not only have a great respect and knowledge of the land (inclusive of the fauna and flora) but also revere the natural world as sacred.

6.8 IRULA The Irula

make their own drums and wind instruments for their

musical enjoyment. The

Kota of the upper Nilgiris generally no longer 21

supply music as they once traditionally did, so the Irula are now frequently employed as musicians at Badaga and Toda funerals. They also make medicinal herbs.

This hunter gatherer community is found in the southern and eastern slopes of Nilgiris, and are also spread throughout much of Tamil Nadu. It is believed by anthropologists that the Irulas were not originally found in the hills but were and are a people more of the plains. Likely they moved up to the hills while doing their slash and burn cultivation. In addition to agriculture such as subsistence farming with tea and coffee, the Irulas also hunt and gather food.

This includes honey collection, which is done mainly with Apis dorsata and Apis cerana.

They also collect medicinal plants and other NTFPs, much of which they gather in volume in order to trade. Overall, their form of livelihood is a mix between hunter- gathering, wage labor, and agriculture, such as rearing cattle and cultivating land. When honey hunting they use much of the same tools as Kurumbas, such as burning leaves as a smoker (they refer to as Raja Tulasi) for protection and making rope adder from certain tree fibres. In this honey collection tradition they also perform spiritual rituals like refusing to eat meat prior to the hunt or praying on the honey rock (the cliff where hives can be found).

In addition, they designate some cliffs as sacred, believing spirits live in them, and thus do not harvest from there but send a small prayer during the season. When potential honey hives are found prior to the collection season they mark with tobacco to warn other people that they comb has been claimed. Once honey is collected, the first of the harvested comb will be offered as a gratitude to the gods in three different directions. The Irulas 22

also are known for the sacred groves that they call “thoga” and their burial sites that they refer to as “koppe”.

6.9 LIMITATION There

are about 36 tribes in the Nilgris. Not all the tribes are taken

into account and the spaces are not designed for all of them. The four main tribes with rich culture and art skills that are deteriorating in the present are the mai focus in this design. There are spaces being provided for the other art forms like workshops and storage rooms for the same. They are categorised under common spaces and can be

used occasionally

by anyone. Temporary Exhibit spaces will also be provided. The proposal aspires to solve various programmatic and social issues that arise for the tribal people.

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7. MATERIAL STUDY SIRE WALL – Structural Insulated Rammed Earth Wall 7.1 WHY SIRE WALL? It takes nearly 100 trees to build a building and 60,000 trees to build the neighborhood buildings. Each year 135 million tons of waste is produced out of building construction. This is enough garbage to fill 50,000 football field. Houses and other building use 40% of world energy.

Right now all the building are filled with toxic substance like volatile organic compounds

in adhesives, paints and dry wall which causes

cancer, developmental toxicant , reproductive toxicant. Formaldehydes in fiberglass insulation,

drywall

mud

and

plywood

sheeting which

causes asthma exacerbation ,chronic respiratory illness and cancer.

Fungicides in drywall, framing lumber and sliding which produces liver toxicant , skin toxicants and blood toxicants. Adding to above a building is made up of many more chemical substances.

Sire wall and walls

is a technique for constructing foundations, floors,

using natural raw materials such as earth, chalk, lime, or

gravel. It is an ancient method that has been revived recently as a sustainable building material used in a technique of natural building.

7.1.1 ADVANTAGES OF SIRE WALL ● simple to manufacture, ● acts as insulators, 24

● non-combustible, ● eco-friendly, ● thermally massive, ● strong, and ● durable.

7.1.2 DISADVANTAGES OF SIRE WALL ● Laborious ● Requires skilled labor 7.2 SOIL STABILIZATION Soil stabilization comprises a variety, and often combination, of modification processes to improve soil properties, including strength and resistance to water.

In addition to compaction, an inherent element of rammed earth construction that seeks to maximize material density, stabilizing additives can be combined with the natural soil. Additives generally fall into two classes: those that materially increase strength and reduce moisture absorption; and to those that reduce moisture absorption and moisture movement but do not appreciably increase strength. Additives commonly used in rammed earth are briefly considered in this review.

7.3 SOIL SPECIFICATION Colour Natural soil is available in a very wide range of colours, including reds, yellows, browns, greys, greens, blues, white, and black. Red colour soils are often preferred. Variation in aggregate colour can lead to non-uniform finishes.

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Though other parameters, such as strength and erosion resistance, are more likely to govern soil selection, colour is an important aesthetic consideration for the client and designer. Natural colours can be varied by using additives, such as lime and cement, or by blending different soils. The use of varying coloured soils has been used very effectively by a number of builders, to enhance the stratified (layered) finish. Use of some surface treatments, such as sodium silicate and PVA, can alter the surface colour, and should generally be checked before main application.

7.4 SELECTION CRITERIA FOR NATURAL RAMMED EARTH A wide variety of sub-soils have been used for natural rammed earth buildings, with the exception of uniform coarse sands and gravels with no fines or cementing agents. For earth wall construction, the soil should contain all four elements. Ideally the soil should have a high sand/gravel content, with some silt and just enough clay to act as a binder and assist soil compaction. Any material coarser than 5-10mm should be sieved out. Previous experimental work indicates that increasing gravel size reduces the compressive strength of rammed earth cylinders. However more research is warranted to define grading for rammed earth, especially maximum gravel size and proportions.

Proposals tend to converge towards a 30%-70% balance between clay/silt and sand proportions. Nevertheless no soil is likely to be ideal with regards to all of the aspects considered and therefore researchers around the world usually publish upper and lower limits for each of the main soil elements. the upper range limits for clay, silt, sand and gravel for rammed earth construction, as proposed by various researchers. In general the percentages are ‘by mass’, though in some cases it is not clear whether the percentages stated by the author were ‘by volume’ or ‘by mass’.

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it is clear that in broad terms there is some agreement on the limits between the main soil elements. The minimum percentage of combined clay and silt should be between 20%-25% while the maximum between 30%-35%. Similarly, the minimum percentage of sand should be between 50%-55% while the maximum is between 70%-75%. Some anomalies can be explained on the basis of different limits for the soil constituents, as stated previously. Based on various experimental data, CRATerre-EAG has produced a graph including grading curve limits for rammed earth construction. The graph is in agreement with the limits stated previously and can readily display when correction of grain size distribution may be required.

7.5 SELECTION CRITERIA FOR CEMENT STABILIZED RAMMED EARTH Soils for cement stabilized rammed earth tend to have proportionally higher sand and gravel content and correspondingly lower fines content. In broad terms the criteria presented are in agreement. For example, a soil suitable for cement stabilization should have a significant sand content, at least greater than 50% and preferably closer to 75%, and at the same time low clay content, typically less that 25%. As in the case of unstabilized rammed earth, these criteria are intended as a broad initial guide for soil selection and include recommendations for soil blocks as well as rammed earth.

7.6 DURABILITY Durability in the context of earth construction means the ability of the structure and all its elements to withstand the destructive action of weathering and other actions without degradation to the expected service life. Rain and frost 27

are the most destructive natural actions causing erosion and deterioration of the earthen elements. Accidental abrasion is also a significant agent of deterioration. Some previous studies have noted relationship between compressive strength or durability and accelerated durability test performance.

7.7 RAINFALL EROSION The performance of natural rammed earth under driving rain cannot be readily predicted in the absence of test data. However, at the same time there is little correlative data between laboratory tests and field erosion. Building element erosion is complicated by various parameters, such as exposure, shelter and maintenance. Two main test procedures have been developed to measure the relative erosion resistance of earth elements, namely water drip tests and spray tests. A third test procedure, based on repeated wetting and drying cycles is widely used for cement stabilised materials but is not generally suitable for natural earth and thus has not been included in this review. A variety of different drip and spray test procedures have been proposed; two of the more widely used for natural rammed earth are outlined here. There is little or no correlative data between accelerated test performance and actual building performance of materials. Consequently, pass/fail test criteria are somewhat arbitrary.

7.8 SHRINKAGE Rammed earth, as all earth building materials containing clay, swell on contact with water and shrink on drying. In both cases failure might occur and hence 28

swelling/shrinkage control is vital. The extent of these phenomena is very much dependent on clay present (type, amount), soil grading and moisture content changes. Only experimental data can confidently predict the percentage of shrinkage expected for a particular soil.

7.9 CEMENT STABILIZATION There various advantages when using cement as a stabilizer. Soil samples gain Strength from both the formation of a cement gel matrix that binds together the soil particles and the bonding of the surface-active particles, like clay, within the soil. High levels of cement stabilisation improve the surface coating and reduce erosion while increasing the cement has a considerable influence in improving the resistance of soils vulnerable to frost attack. However there are notable disadvantages using cement. The permeability of most soils is reduced and hence the natural ability of earth to allow passage of moisture throughout the soil mass is also significantly impaired. Environmental impact of cement production and reduced ability for recycling of rammed earth are also significant arguments against widespread use of cement in rammed earth construction. Less significantly, thermal conductivity, compared to lime stabilized blocks, is reportedly increased.

7.10 THICKNESS OF WALL Internal

External

125mm

200mm

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7.11 DESIGN 7.11.1 OUTLINE Site characteristics, including local climate, topography, wind direction, and Sunlight orientation, have an important influence in the design of successful rammed earth buildings. These factors, together with others, will influence the way the house is located and orientated within the boundaries of the site. The architectural plan is also of course influenced by client requirements of aesthetics, functionality, comfort and efficiency.

7.11.2 SITE CHARACTERISTICS Design in sympathy to local site conditions is now widely recognised as one of The fundamental principles of good ‘green’ building design. This review does not seek to repeat these principles in any significant detail here, but rather outline their influence on design and construction of rammed earth buildings as mentioned in available published literature.

7.11.3 LOCAL CLIMATE Local climatic conditions have a significant influence on design of successful low energy buildings. Rammed earth is generally considered to be well suited to passive solar design as its high mass and hygroscopic nature contribute to regulation of internal temperature and humidity, reducing the need for active heating and air conditioning systems. Most sites will experience a wide variety of weather patterns over the course of twelve months. Climate appropriate 30

architecture should reflect that variety. The very basic principles of good architectural design as a response to the local climate, in the context of rammed earth, is summarised as follows: __ in hot humid climates, provisions for wide porches and large screened windows with cross ventilation should be made; __ in hot dry climates, thick walls, small windows and night-time ventilation should be utilised in order to reduce cooling loads by using the thermal mass of the walls to counteract daytime heat gains; __ in climates where the demand for winter heating exceeds that for summer Cooling and the winter days are typically clear and sunny, large south-facing windows (in the northern hemisphere) and thermal mass floors should be used to reduce heating loads; and __ in regions where winters are long, cold and grey the best approach is to build small well-insulated buildings with low ceilings and a minimum of exterior wall surface exposed to the weather.

7.11.4 SITE TOPOGRAPHY The direction and severity of natural slopes on a site is an important consideration. A flat site, away from watercourses, allows greatest flexibility when orienting a building and can simplify the construction, since all foundations can be of equal size (when subsoil conditions are also uniform), and the site can often be more readily accessible during construction. Hillsides can stimulate internal building air movements from prevailing winds, though cold air tends to gather at the bottom of slopes and wind velocities increase further uphill.

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7.11.5 ARCHITECTURAL PLANS Design layouts for residential houses around the world are as a diverse as the natural climates, cultures and wealth of the people that live in them. As energy efficient buildings should seek to adapt to the individual characteristics of their siting any published plans for rammed earth buildings will have limited general application. Few architectural plans have been published for rammed earth houses. The Indian National Buildings Organisation produced a typical recommended layout of a modest 20 m2 rammed earth house intended for landless rural families. Further those available from drier and hotter climates, such as south-western USA and Australia, probably have limited application in the UK. Some of the most significant plans available are those produced during building of the experimental cottages in Amesbury, Wiltshire. Ten experimental houses, including eight two-storey chalk pisé houses, were built between 1919 and 1921. As part of the experiments straw, ‘mud’ or cement were also used in some of the buildings. External loadbearing walls are formed from 450 mm thick chalk pisé. Internal space is maximised by using thinner partition walls of fired clay brickwork. Reinforced concrete lintels may be either pre-cast or cast in-situ.

Care should be taken to ensure that adequate reinforcement and adequate cover is provided for the beam in accordance with the local codes and regulations. The concrete lintel can be seated directly on the earth wall or on a mortar bed and, as a minimum, Standards Australia recommends a lintel width equal to the width of the supporting wall. Detailed reinforcement proposals for concrete lintels for various loading cases are included.

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FIG 4: Anchor for doors and windows

FIG 5: Details of Window jambs

FIG 6: Details of door jamb sections

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FIG 7: Details of door head section

FIG 8 : Reinforced concrete beam roof connections

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FIG 9(a): Pneumatic rammer FIG 9(b): Modern concrete shuttering for rammed earth

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8. SITE LOCATION

FIG 10: Map

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FIG 11: Macro size view of site from Google Maps

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FIG 12: Site Top View

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FIG 13: Site Image 1

FIG 13 - Site image 2 43

FIG 13 - Site image 3

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FIG 13: Site image 4

Fig 14: Sun path 45