Beautiful Bamboo. By Pietrus Nimbus.

Beautiful Bamboo.

By

Pietrus Nimbus.

Preface.........................................................................pag. 5

Bamboo plant...............................................................pag. 6

First testimony and constructions system....................pag. 9

Traditional constructions...............................................pag. 31

Contemporary constructions.........................................pag. 52

Index:

Humanitarian bamboo & Prefab systems.....................pag. 92

Modern systems and engineering................................pag. 109

Mechanical proprieties of bamboo................................pag. 160

Design & Bamboo.........................................................pag. 170

Bibliography..................................................................pag. 179

Bamboo is considered a material that as not long life.This is true if the construction is wrong and it's incorrectly located under direct sun light and exposed to humidity. There are example of bamboo durability that can be seen in construction of 100 years ago, still in good conditions thanks to right construction and upkeep.It is common to associate construction of bamboo with the word 'primitive'. But the of design with bamboo covers a wide range of architectonic possibility. From classical and simple designs to modern and complex projects.

We have to keep in mind that bamboo is a material that nature offers in an almost unlimited quantity.Moreover its use requires minor economic and energetic efforts.In determinate case it can be a valid alternative in contemporary architecture solution but it also can be the solution for problems such as shortage of residency,sustainable architecture and temporary houses after natural disasters.

Preface.

Bamboo plant.

Root.

Cane.

First testimony and constructions.

First Constructions.

The original forms are considerate today classic but nowadays those are still used frequently for simple refugee or just for a place to selling .Examples are the one whit a big round top carried by one central mast or the ones with the rectangular top carried by two mast.

Construction in Asia.8000 a.c.The first construction, made of a round top carried by one central mast, developed in a new structure made by four pillars and four beams of wood that work as support for the bamboo witch give the conic shape of the roof.

Japan.

Adobe house with beam and poles. 3500 a.c.

In general is very difficult to understand if a prehistoric structure 3000 years ago was build by bamboo or by wood,for the reason that both have organic nature that make the process of decomposition very rapid.There are reasons to believe that this primitive houses were made with bamboo

Olaf Holm(1985) told us that the most ancient house was found in Real Alto,Ecuador, build 5.000 years ago. It had oval shape and an height of 4.50m. Walls were made of mud and straw.The ones who developed this technique were the indigenous ancestor that lived in central America more than 6.000 years ago.

The natives were excellent bambu builders. To save their houses both from inundations in the wet season and from the dangerous animals of the jungle, they elevated their houses from the ground.

3.500 years ago professor Merino found in Canton Milagro,Ecuador,pieces of mud with the mould of bambu panels . This was the rest of an ancient wall made by panels of bambu fulled with mud and staw.

The adobe houses was the solution traditionally used in the seismic zone of south America. From Colombia to Bolivia. The same solution were used in Indonesia, land of volcanoes and earthquakes.

To build an adobe house are used poles ,each at a distance of one step from another, linked horizontally by squash bamboo and finally filled by mud or clay.

The Adobe building system imply a big weight, for this reason,in construction higher than one floor the mud is eliminated from between the panels of bambooAdobe is very vulnerable by water,rain and ascendant humidity. Its required that walls don't touch the ground and a good eaves that will repair it.

Arch. 600 a.cThe only nation who used the advantage of bamboo's flexibility for the construction of temples and houses was India. It happen in the Vedica Era.

The Indians discover that the superior part of the cane was stronger in compression than the inferior part,the base, for the reason that the superior part has a bigger number of fibers. In order to create more attractive designs,Indian builders started to use the canes in a way that could generate arcs of the shape of loto flower.

The Hindu tradition has its roots in the Vedica era. Around 600 a.c.. In those years many cultures and populations fuse together in the plains of India. Once they become farmers, they used to have shelters made of bamboo and simple roofs of leafs.This simple and modest houses were the starting point of Indian architectureThere are three styles of the construction in this Era. Those are characterized by the different shape of the roof.

In the first period houses were build like bee hive, a circular bamboo wall hold together by bands of wicker and covered by a thatch or a cupola.In the second period, for reason of space, the diameter of the plan couldn't be bigger, for this the house become bigger just in one direction, taking the shape of a rectangle with a barrel roof and bended straw.In the third period the wood construction adapted for bricks and stone, while the roof substitute straw with panels of wood or ceramic.These three kind of architecture reflect also the class of the owner. The first typology was the one reserved for the low class, the second for the middle class and the third for nobility,temples and mosque.

In order to give the shape of barrel to the houses of rectangular plan,t was used a kind of belt that press the arch until it take the shape of a flower petal or horseshoe.

The elasticity of the roof was one reason for the artesian of India to adopt the form of loto or horseshoe. But there were more reason. The petal of loto ,in fact, symbolize the sunrise from sea or from the waters of the divine Gange river. The adoration for the born of the sun is part of the rituals of India since prehistoric time.

There four essential elements in the ribbed vault that guarantee the stability of all the structure:

1- the central pole has to be strongly joint in the ground or on a stable surface.2- bamboo ribs3-the relation between the ribs and the point of strength of the cupola'4-the lid that provides the ribs to the crown of the cupola.

The elasticity of the roof was one reason for the artesian of India to adopt the form of loto or horseshoe. But there were more reason. The petal of loto ,in fact, symbolize the sunrise from sea or from the waters of the divine Gange river. The adoration for the born of the sun is part of the rituals of India since prehistoric time.

The loto cupola.

This image of Vedica village shows how the different construction use bamboo The first house was the one of circular plant, with bamboo cupola, that developed in the rectangular plant house with a barrel shape roof.

The stone cupola of Taj Mahal derives from the ancient cupola made of bamboo.

Reinforced works 850 d.c.

The Chimu' civilization, from Peru', central America,could build houses until 9m of height. They were the first in using vertical joints,expansion joint and big bamboo in walls as reinforce them in order to prevent damages from earthquakes.

In the upper image we can see the use of bamboo inside the adobe wall as wall the expansion joint.

The verticals joints were made every 5 m. In this time, people already know that those kind of articulation permit the movement of big vertical walls in horizontal direction. More over the wall could expand or decrease during the change of temperature day-night. Bamboo reinforces, worked as metallic reinforces works today. This device gives stability to walls and elasticity during earthquakes.

This technique was known from more ancient time,since already Chinese used to reinforce their adobe walls with bamboo of small diameter,3-4 cm, putted horizontally and vertically creating a grid perpendicular to the ground.

The maximum experts of this technique were the Chimu', that used a spice of gigantic bamboo in the big city of Chan Chan. In this way they could build big building instead of the simple home of the Chinese.

Chan Chan city. Peru'.(founded approx 850 d.c.)

In 1535 Pizzaro and his 'conquistadores' arrived to Peru. Also Chanchan city was attacked but the big bamboo walls and the perfect skills of the Chimu in build arms and new walls very fast gives to Pizzaro a rough ride.

Traditional joints.All the construction seen until now, were developed in those ancient time in order to guarantee some specific needs given by time and place. From the point of view of joints, is the same, all the kinds of union are quite simple and are still used in many parts of the world considering that their static behavior is satisfactory.

The unions that we will see are realizable with a limited number of tools, like machete,parang and vegetable ropes.

Cut.Union through cut perpendicular to the longitude.

Union through layered cut. The support between the pieces increase,in that way longitudinal work result better distributed

Union trough oblique cut,the friction and cohesion between the two parts increase.

Union through oblique layered cut. The joint between the pieces is more developed and the union will be more rigid.

Fish mouth.The fish mouth is used to unite one extreme of the bamboo cane with another perpendicular. To get this kind of union is necessary to mold the extreme of the cane in a round shape. The important advice is to obtain more support surface as possible, in order to increase the solidarity work

Cut with flap.In order to get a more solid union it's possible to mold a flap, a short segment of the same cane positioned in the two extremes. It function is to join another cane, previously perforated at 2-3cm upper the inferior node.

Tied.

The tie trough simple node can be made simply with the force of tension given by hand. This union no needs of tools.

There are two kind of union through rope. The basics that don't require any tool and the advanced. These need a tool that can perforate the bamboo cane.

It can be done a double tying for the principal node. Is sufficient to make it just in one node if the union is perpendicular.

Tied.The tie trough node with perforation, requires the execution of one fissure passing trough the cane. It's recommended for angle unions.

Perpendicular tied.

Oblique Tied.

Wedge.With union through wedge we refer to all those who requires an external element that pass through the bamboo cane.

In traditional union the wedge is made of the same bamboo cane. In this way the dilatation and contractions given by changes of temperature and humidity, will not affect the cane. If the deformations are the same we will not have any damage.

Traditional Constructions.

While the neolithic era was arriving at his end also in the more remote parts of New Guinea, the bamboo era was still live and his use was essential in the economy of many rural parts of Asia,Africa,America. Moreover,in many tropical country ,many parts of the homes were build up with bamboo both in rural zone and urban zone.

Tongkonan. XIII sec.The Toraja are an ethnic group that live in the mountainous region of South Sulawesi, Indonesia.Tongkonan are the traditional Torajan ancestral houses. They stand high on wooden piles, topped with a layered split-bamboo roof shaped in a sweeping curved arc, and they are incised with red, black, and yellow detailed wood carvings on the exterior walls. The word "tongkonan" means 'to sit' . Construction of a tongkonan is laborious work and is usually done with the help of the extended family. Tongkonan are the center of Torajan social life. The rituals associated with the tongkonan are important expressions of Torajan spiritual life, and therefore all family members are impelled to participate, because symbolically the tongkonan represents links to their ancestors and to living and future kinIn Toraja society, the funeral ritual is the most elaborate and expensive event. The death feast of a nobleman is usually attended by thousands and lasts for several days

Kinds of traditional roofs.

One other characteristic of this kind of building is that the big frontal projecting are secured by a pole direct to ground.

According to myth, the first Toraja house was constructed in heaven by Puang Matua, the Creator . It was built on four poles, and the roof was made of Indian cloth. Next, Puang Matua ordered the construction of another house, on iron poles and a bamboo roof. When the ancestor of mankind descended to earth in the southern half of Toraja he imitated the heavenly house, and a big house ceremony was held for the occasion.

Making an house wich roof w has two ends bending upwards. This particular form is explained in various ways. The first story stresses resemblance to a boat - since, according to myth, the ancestors of the Toraja people came by boat from the Mekong Delta in South China - the second story claims that the arch-shaped roof looks like the sky. This is, indeed, reflected in some prayers by the ancient animistic belief Aluk Todolo.

Two myths to explain the toraja house's shape:

As described above, the creator Puang Matua is associated with the North, and therefore the tongkonan must also face North. The South of the house is associated with the afterworld (heaven, or Puya) and the ancestors. The West and the East are associated with the left and right hands of the human body, but also with the world of the gods (East) and the ancestors in their deified form (West).

Bamboo roof in Sumatera and Sulawesi.

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The bamboo roof is totally supported by the wood columns.

Tana toraja House,south Sulawesi. Indonesia.

A. Pasermah House,Sumatera.Indonesia.

B. Tamimbar House, Maluku islands. Indonesia

Twisted beehive. Ethiopia XIIIsec.

In Ethiopia,Africa were developed two kinds of home twisted with bamboo Chencha house and Sidamo House .

The high of Chencha house can reach,sometimes, eight meters from the ground and uses to have 6 meters of diameter Builders dig a circle in which the bamboo are insert at 10 cm distance each other. They start to twist horizontal rings every time smaller until the beehive is completed. To finishing it builders use a layer of cane leafs.

In this house there isn't central supports or poles.

Do-chala. Bengal XIV sec.

The majority of the building were made with the materials of the area, bamboo and straw, consisting in a rectangular plan covered by a curved thatch.

Influence of bamboo construction in Islamic architecture.

Like for the loto cupola, the form of the dochala was created by the artesian from India,much more before they converted to Islam and bring those shape to the Islamic temple,the mosque.

In India people were used to use straw and bamboo for their constructions but when the Muslims arrived, they bring their already formed tradition and imposed their building method to local populationFrom this collision we can extrapolate three distinctive character of the building in order to understand the consequences and the evolutions of bamboo constructions.

1. Architectonic shape

2.Architectonic design

3.Construction's elements

3. the pointed arch, the mihrab and the vault of the Islamic architecture are all elements that seems to have they ancestor in the shapes of the bamboo cane put under tension.

1. In Bengala's houses we can see the shape of the roof that is kind of curved,creating also big eaves.The curve of the roof can be reach tanks to the elasticity of bamboo There are two kinds of roof :the Chauchala, that has four sides and the Dochala that has two sides and ends in a gable roof.

This kind of roof-shape contributed to influence the styles of Hindu architecture at the time they start to use stone and bricks

2. The peculiar design of Bengali' house also take inspiration from the first bamboo huts present in the area.

There are two main characteristic in those huts that have to be considered:First, the four corner poles are joined together by diagonal long bamboo canes.Second,the presence of niches on the wall surfaces and a continuous molding at the lintel's hight.

1. Original roof with straight edge. 2. The straight top is curved and gives the docha-la shape at the roof.

4. When the Chauchal roof was adopted in a square shape plant the vault was born.

3. The straight faces of the dochala roof are curved as well, giving to the top the shape of 'roof chauchala'.

Pole and beam. XVI sec.

The system of couple and knuckle creates strains that can transfer the weight of the roofs to buildings .This constructive method was originally made with wood but can be easily transferred to bamboo.

One of the advantages given by use of bamboo instead of wood is in the joint of crossed poles. When using wood,a big bending load will weight on the structure's bolts.Bamboo has a very hard external skin that makes it more similar to a metallic tube that a wood. In this way is very difficult that the bolts of the crossed joints are deformed. With additional mortar in the cell in which the bolts are we obtain a satisfactory fastening.

With this constructive method it is possible to fabricate structures of several floors.

Bamboo houses in Colombia.

Colombia, probably is the only country were the

bamboo is used in all the components that are

making an house. From the principal structure,

poles, beams,panels for the floor, structure and

bars of the roof to walls.

Differently from Colombia,in Asia, the principal structure of houses and buildings are made of wood or stone and the bamboo is reserved for the making of roofs and finishing of walls.

Bamboo structure for a traditional rural house in Caldas,Colombia.All the structure is made of bamboo.

Manizales, Colombia.

Manizales and the majority of the cities of the province of Caldas grow on the beautiful landscape of the Andes. The pendent is very high, for this reason is necessary to project a kind of weaves. A series of substructure were built, until the hight of 15 meters and they worked as supports for the houses. This houses were built by the campesinos that used the enormous reserve of bamboo in the area.

View of houses in the province of Caldas.

Lateral Section.

China. XVIII sec.

Nowadays in the majority of southeast Asia bamboo isn't anymore used to build the principal structure of the house.

Bamboo is used for the construction of the roof and for interior and

exterior walls.But is evident that pagoda's roofs are now built with wood or concrete ,although originally those were made with bamboo.

More precisely in China,all the structure, included roofs and walls are made with wood. But in many case the walls are made of adobe reinforced with bamboo cane of small diameter.In the past, the more common material used in all kinds of constructions, was bamboo,included in China.

In 1975 some students from the University of Jakarta ,showed the reconstructions of the 'stick roof' of the XVIII were made with bamboo.

Reiner Graefe said that G.th Hoech showed is theory in 1913, demonstrating that the shapes of the curved Chinese and Japanese roof were the congruences of the use of very elastic bamboo stick, for beams,poles and bars.

One of the most interesting description about ancient house in China can be found in the book written by Viollet le Duc in 1875,”Histoire de l'habitation humaine”.The house,probably owned by a rich family, was built with extensive use of bamboo.In le Duc's descriptions we find plants and quality perspective of the details of constructions and of the bamboo grid that closed all the openings allowing the free circulation of air.

The house had a porch(P) elevated some cm respect the ground line. From the porch the people could enter in the living room(A),where the roof was enhanced in order to get more light from the exterior wall.(A) is opened to two lateral rooms(B)lower in high and with small corridor for access to two covered balcony(C),one of them next to the river. Behind the gallery, one bigger corridor(D) brings to a terrace(F),two rooms(E) and to one larger and lower room(G) destinate to cook and larder

Ones of the most interesting details of the house are the skeleton of bamboo of the Vierendell structure that is located in the porch of the home and the nice frames of rigid bamboo of the living room that are supporting the roof.

Modern and Contemporary Constructions.

Correct constructive process.

Harvesting, storage and drying.

Bamboo preservation.

Traditional methods for preservation.

Chemical methods for preservation.

How many kg of dry chemicals remain in 1 m3 bamboo after treatment.

Generally speaking a good chemical preservation can increase the natural of bamboo to 15 years in the open and 25 years undercover. The chemical most used are CCA and Boric acid. Let see in detail these methods.

CCA.

Boric acid.

Chemical methods: open tank method.

Chemical methods: butt treatment method.

open tank method.

A.

B.

Chemical methods: boucherie method

Alternatives methods.

There is a debate either the boric acid is toxic or not.Boric acid has low toxicity to humans through ingestion or inhalation. Median lethal dose (LD50) rating of 2,660 mg/kg body mass for man. Boric acid is poisonous if taken internally or inhaled in large quantities. It is generally considered to be not much more toxic than table salt. Some ethnic groups use it however as a food additive. However in some countries it is requested to farmers and restaurateurs not to use it because of unacceptable risk to consumer health.In France, the boron content should not exceed 1 milligram per liter according to health standard for drinking water. At high concentrations it is irritating to eyes, skin and respiratory tract where short exposure but may have effects on the kidney in cases of prolonged or repeated exposure. The European Community decided to amend its classification as repro-toxic category 2 and to apply the risk phrases R60 (may impair fertility) and R61 (may cause harm to the unborn child).The techniques of treatment of bamboo shown below are an alternative to preservative treatment with use of chemicals.

Alternatives methods:Treatment of bamboo with limewaters.Mix the lime (slaked lime) with water. It is sparsely soluble, it is necessary to stir the mixture for some time. This step results in a white solution called milk of lime, which is a suspension of calcium hydroxide particles in water.To eliminate the unsolved lime in suspension,proceed to a decantation of the milk of lime for 24 hours. As a result we obtain the lime water, a clear solution.Lime water is the common name for saturated calcium hydroxide solution (Ca (OH) 2)In contact of carbon dioxide (CO2) it will form calcium carbonate (CaCO3), which can be seen as a white film on the surface of the lime water.

Once limewater is ready, it is transferred by gravity into the basin where is placed the bamboo to be treated. Bamboos are impregnated with lime water by soaking for one week.As with borax, it is important to perform this treatment on freshly cut bamboo. Indeed, unlike wood, bamboo undergoes anatomical changes and begins to shrink once it begins to lose water.Sap in the vessels is precipitated, clogging the openings to the adjacent tissues. This reduces the treatability of bamboo and therefore the diffusion of preservative agents in the cells of bamboo.

Alternative methods: Treatment in boiling linseed oil.

The slats of bamboo are soaked in linseed oil heated to between 100 and 120 ° C.The treatment of bamboo by oleo-thermal process is to not developed mainly due to the excessive cost of energy to boil the oil in large basins.

Alternative methods: Thermo-treatment.

The principle of the process is to heat the bamboo in an autoclave at a temperature high enough (for bamboo between 150 and 200 ° C), in anoxic condition and to regularly inject steam to avoid the bamboo to ignite. Bamboo is "cooked" in some way and stabilized while remaining solid. Its ability to absorb water is reduced by half.

However, heating the bamboo at high temperatures makes it stable and virtually rot-proof. It thus makes naturally resistant to borers, termites, fungi and moisture.Bamboo products treated by this method can also be used as a structural element of a building. But bamboo from thermo-treated tends to reduce strength and flexibility, and their implementation in structure requires special precautions (such as use of larger section).They are also ideal for flooring, decks, exterior, siding etc.

Treatment on the surface.

Development of joints techniques.New techniques, new materials and new tools produce new kind of joints,respect the ones that we saw until here,that are more sophisticated,solving easily problems.

Wedge.

Wedge unions exist by perforate two canes of similar diameter and shape with a smaller cane that keep them together.

Cut.

Simple cut of the cane. It can be used as stagnant joint for hydraulic engineering through exterior or interior pipe connections.

A small bundle is introduced in wedge unions in order to stiffen the node.

Used also in continuous or angle joints.

Wedge.

Bundle.

The joints through bundles are developing constructive concepts as tension directions and reinforce of weak points.

Simple joints will became more sophisticated.

Bundle with wall.

Cross bundle joints are developed also with the help of further materials apart of the only use of bamboo cane .

Metallic joints.

There are many metallic joints,but before XIX century the most used was with screw and flat bar.

For good conservation of bamboo is important that it doesn't touch directly the ground.

For the good execution of foundations we will make concert in which a bolt has to be soaked and that will have the function of holding the support pillar.

Foundations.

After inserting a transversal bolt in to the last part of the pillar ,we will join it to the holding bar.

After that we will hole the last piece of the bamboo cane and we will fill it up with mortar.

Execution of a pyramid base foundation.

Details of foundations on sloped ground.

Details of foundations. How avoid humidity.

Another system for avoid the humidity for capillarity, consist in filling up the last two parts of canes with mortar. Once it set, the last half of the last part of the pillar its cut away.

Concrete foundations for flat and pendent grounds.

Bending,shaping and flatting techniques.

Floor structure.In the primitive house the floor structure was mad only by building above the ground of compacted hearth,covered by leaves and bamboo mat.

This system can be increased by elevating the floor ground upper than the ground level in order that the floor can't touch any superficial water.

It's also possible to fill up the space between the canes of bamboo placed in two directions, with clay. The layer of clay will work as a barrier against the humidity coming from the ground. The upper side of the clay block as to be leveled but not compacted as it will be covered by bamboo slabs.

An elevated floor is more convenient and hygienic. More over it form a storage space for materials,tools or animals under the house.

The canes of bamboo used as beams of floor structure are more light and elastic that the conventional solid wood.

In order to avoid the ground's vibrations, the space between two beams hasn't to pass 30-40cm.

The separation between beams has to be chosen depending on the type and the diameter of the bamboo cane.

Floor covering types.

Walls structure.The requirement that the walls and the opening have to satisfy are the protection against animals, torrential rains,wind and sun. At the same time they have to offer an optimum ventilation, illumination and a way out for smoke.

Wall has also an important aesthetic role.

In the rural areas the acoustic requirements are not so important because there aren't unpleasant emissions.

The most common type of wall is the one made of wattle and daub. Basically a grid of wattles or bamboo canes covered by clay or mud. Some typology of walls can be used also as roof cover.

Wattle and daub wall.

Walls made by grids of bamboo.

Paneled walls.

Roof.

Roofing.

Bamboo leafs.

Bamboo long strips.

Palm leafs.

Bamboo short stripes.

Straw.

Bamboo's long strips roof.

Bamboo's small strips roof.

Bamboo leafs roof.

Straw roof.

Palm leaf roof.

Humanitarian Bamboo

& Prefab system.

Bamboo for humanitarian constructions.Modern joints and new techniques allow architects to play with the shape and the size of the modern constructions made of bamboo.shell shape, curves and parabolas improve so much on the freedom of design.

In China bamboo is considered a friend of people,in Vietnam his brother and in India the wood of the poor.In Asia bamboo is a fundamental source for the economy. Of the 10 millions of tons produced in all the world each year, most of it it's produced in Asia.

Although Asia is the first producer and consumer of bamboo also in some countries of America it's use is very common.

After so much years of traditional and modern construction in countries such as Mexico and Colombia it's start to elaborate normative for a future industry of construction. In order to guarantee the uniformity of the prime material there are progress in theme as preservation, environmental protection, sustainable harvest and descriptions of correct unions and joints. These normative that are still to be developed and yet far to be widely applied in everyday construction are known as the “ICONTEC normative”.

As to be mentioned that the start in the direction of develop serious normative was given by the observation of the effects of earthquakes both in Asia and in Colombia. The people saw that most of the construction made with bricks and reinforced concrete collapsed, while the one made with bamboo and concrete resisted the seismic energy. After this facts the scientific community of all the countries that are menaced by seismic and earth movement start to intensify investigation on this material.

A sustainable constructive system depend ,between others factor also by the availability of the material in the place of the work. The high cost and the length of transportation stopped the use of bamboo in Occident Even that, in Germany,where bamboo construction is officially permitted, architect Simon Velez developed important constructions.

The optimum mechanic qualities of bamboo make it an excellent structural potential.United Nations estimate that at least 100 millions of people are careless of houses. The future prevision on these theme are pessimistic. In fact statics says that in 50 years the situation will be worst.

Bamboo grow up very fast in erosional grounds and sometimes in contaminate grounds,recovering it in 10 years. It can be an hope in the poorest region of the planet

Prefab.

The deficit of house is one of the biggest problem in countries in south America and in the overpopulated south east Asia. For example, only in Nicaragua there is the lack of 500.000 houses and after January 2010,Haiti island needed over 1.2 million houses.

The bamboo plant is ideal for be used in all the countries over mentioned,it's flexibility make it a proper material for construction in seismic areas. Of the same importance is is very low level of carbon footprint, even more if compared with traditional materials such as iron and concrete.

A part of that its also advantageous to use bamboo because it need short time for growing and also for the assemblage and construction

Reduction of construction time and low cost are priority in zones of the planet less developed. Moreover, prefab houses minimize the need of specialized workers.

In summary there are five vantages that explain the success of prefab houses:

-Rapid time of construction, with no need of specialized workers.

-Comfort with the variation of temperature. Bamboo if right integrated with ventilation and covering of roof absorbs and reduces heat.

-Good structural behavior against hurricanes and seismic activity.

-it's an environmental friendly material, it has low carbon footprint and even if industrialized for prefab, keeps being a sustainable house.

-and last but not least, it's low construction cost.

Prefab houses in Ecuador.

In 1981 the city of Guayaquil had a population of about one million of people,60% of them, living in bamboo house, in the poor district, without water facility.

Prefab in Ecuador.

The solution to this problem came with Oscar Idalgo that in 1984 achieve to develop an experimental program of housing in Guasmo, a very poor district of Guayaquil city,where people already were living in bamboo house.

This program demonstrated that with financings from government it's possible to construct houses of high quality and give stability to the families that earn only the minimum salary.

This factors where successful :

- small shops and workshop were placed in order to keep busy a group of families. Working 4 hours in this tallier the families could earn enough money. These was used to pay government the term loan for construction materials.

-all the families had to collaborate in the houses construction.

- a prefab system doesn't require specific knowledge, the construction was made following precise instructions.

-the houses were designed in a way that they could be build and developed in different steps.

-first step was the building of a basic unity of 3 for 6 meters,that was including kitchen,toilet and living room,used as well as sleeping and dining room.This basic unity could be increased by adding one or two dormitory.

For the water problem, the solution consist in furnishing each prefab house with2/4 metallic tanks,in the front of the house and the street.A water track filled up the tanks.

Prefab in Ecuador. Plants.

House with one dormitory. House with two dormitory.

details.

Prefab house process: House type I

Prefab house process: House type II

Prefab in Colombia.

After the eruption of Vulcan Ruiz in 1985, part of the city of Armero was reconstructed of the through prefab house system. All the houses were placed in the different levels of ground.

Prefab in Peru'.In the rainy season of 1983 the north of Peru suffer many floods of his cities. Particularly La Arena city, whose population had to emigrate on the dunes of a desert zone where born a new community of 3000 people and known as Las Malvinas.Under the direction of architect Guzman reconstruction of houses and school started.The reconstruction made with prefab of bamboo has the particularity of having all the roofs with a pyramidal shape, giving to this house a characteristic aspect.

Prefab in Indonesia.

In 2010 the Vulcan Merapi erupted, near the city of Yogjakarta. Several cities were compltely destroyed leaving only ashes. In the district of Muntilan were build houses for the families who loses theirs.

Each house is build for two parents and three or four children. We have ten houses and a common bathrooms. On the rear of the houses is placed the kitchen The red color denotes the zone for the father and the mother, the blue color is the zone for the children, the yellow indicates kitchen and storage , while the green the common spaces.

Prefab Indonesia.Magelang Regional district had also to face the disaster of Merapi Vulcan.Architect Pradipto shaped 10 building houses on stilts, each measures 4x6 square meters, occupying an area of 1,500 square meters, and spent Rp 150 million(15.000$). The building has a height 2x3 square meters, consisting of 2 floors, 3 bedrooms, 1 living room, and a kitchen. "We try to provide facilities to keep them from becoming a second victim during a stay in the shelters" he said.

Works finished in just 1.5-month process under the direction of the architect, that involved also 30 students from various faculties of UGM. Due to the emergency and the need of rapidity the bamboo skipped the normal process of impregnation and treatment for his good conservation.Even that,according to Pradipto,the building shelters can be used up to five years,resistant to rain, wind, and earthquake. " All connections use bolts and makes those bamboo constructions so resistant to wind, rain, and earthquakes, "he explained.

Prefab Thailand. Butterfly Bamboo Homes.

Humanitarian design organization TYIN Tegnestue from the Norwegian University of Science and Technology conceived the project in response to a need for more dormitories for Karen refugee children in the village of Noh Bo on the Thai-Burmese border. The six woven bamboo huts, dubbed Soe Ker Tie, or The Butterfly Huts because of their “winged” appearance were designed with the children’s happiness and health in mind. As simple as these new dorms may seem, they provide something wonderful for a growing child.

Aside from giving 24 orphans brand new homes, the huts are pre-fabricated and assembled on site with sustainability in mind. Most of the bamboo used is harvested locally and woven in the same way that is traditional to the area. The special flapped roof of the Soe Ker Tie House is conducive to natural ventilation. Since the roof also collects rainwater, areas around the huts are more useful during the rainy season, and water can be stored during drier periods. Using foundations cast in repurposed tires, each hut is raised above ground level preventing issues that could arise due to moisture and decay.

Modern constructive systems and engineering.

1. Special structures.

2. Parabolic and hyperbolic structures.

3. Tensile structures.

4. Shell structures.

5. Curved structures.

6. Combined structures.

While traditional structures are based on bi dimensional building method , in contemporary design it's time to experiment with three dimensional structures.

Special layers,shell shaped doubled curved and special structures. In this kind of structures we find new needs of the joints since those unions are supporting no linear stress and heavier punctual stress.

There's also the challenge to find the best way to economize the whole building process.

Designers and architects experiment the possibility of mixing bamboo with other materials such as glass, fibers, steel...

In order to resist to those, over mentioned,three dimensional stress, bamboo joints need bolts and internal reinforces, like injection of concrete, as well as external reinforces like fiber layers or synthetic resins.

Special structures.

Structures with three dimensional truss answer very well to stress generated by earthquake or wind.

These kind of structures use “Cone joint” in order to transmit loads to ground.

In cone joint all the stress are transmitted to a central axis and conducted to a ball-shaped connector, forming a reticular structure.

Detail A.

For the execution of this joints are used bolts, or metallic sheet, concrete and metallic cone(aluminum).

We insert the metallic cone, with the bolt, in the extreme cut of stalk, introducing mortar into the node trough small holes previously made.This kind of joint can be used in special structures and domes, but for bigger structures is used main-stay like that shown on detail A, with additional mortar inside the node and a bigger bolt.

Domes.Consisting in a geodesic dome whose proprieties are really advantageous for sustainable and bioclimatc buildings.

Enclose a big volume of space with minimal material, is the kind of structure that use less material reaching the maximum habitable surface.

Moreover, dome shape is the best shape for keeping inside heat. It's advantageous also regarding natural ventilation that freely circulate and ease heating or cooling the space.

The geodesic dome was invented and developed by inventor Buckminister Fuller , that in 1951 reached a method for construction of spheric surface considering surface of the sphere as a series of icosahedron. Icosahedron is the solid from which we can obtain the maximum number of equilateral triangles .Triangles,from a structural point of view are light but very resistant

Fuller designed building from his concept of geodesic domes based in simple assembling of standard elements. We can adapt his method on bamboo structures arriving to very cheap bamboo structures.

Hanger.

This kind of structures are ideal when we have to cover big open surfaces.

These kind of structure resolves the tensile stress of the corners through compression and tensile of the reticular tress.

Parabolic and hyperbolic structures.

Parabolic and hyperbolic structures are the ones that form a curve similar to an hyperbole and a parabola .These kind of structures are generally used for roofs. These covers, made with materials like steel have a really big weight, but if we use bamboo for the structure, it will be very light.Studies demonstrate that the flexibility proprieties of a bamboo cane is much more better if we use all the cane of bamboo,in all his longitude, instead of cutting the cane in smaller pieces.

If we notice the stress preallocated by wind we will be surprise in seeing the bending of the cane without breaking.This natural elasticity increase if the cane are dry and comes from the fact that this plant has to survive to the strong tropicals winds.The elasticity factor is an important advantage if we will use bamboo for roof structures that have parabola and hyperbole shape.

Jorge Stamm. Bali.

Roof is made previously on ground. After it's terminated its elevated on poles that are fixed to ground by concrete foundations.

Jorge Stamm, in Bali, proposed a construction made hyperbole and parable shapes. Reaching good results.

A building work of 14x14 meter with only 4 points of support was made at first. The primary structure has 14 cm of diameter,while the four curved surfaces are set up by less wide bamboo,has it has just 7 cm diameter.

The design had drip from where water came inside, in the point where were placed the four supports.The secondary canes were eliminated and the membrane was joined directly to the primary structure.

Temporary refuge. Ming Tang.

After the earthquake that hit China in may 2008 those temporary refuge were born. Also known as “folded bamboo houses + paper houses”,designed by Ming Tang.The request of the Govern of China, to build 1.5 million temporary shelter for the victims of the earthquake, was accepted by Ming Tang that proposed a design, with the characteristic of easy production,low cost and abundant of material. The big flexibility of the entire cane made this structures stable and transportable. Ming Tang show us the high potentially of bamboo using it again in a prefab system but at same time adopting the new engineering method, as he use hyperbole structures. Once finished the structure,this is covered by other sustainable materials like recycled paper and organic fibers.

Development of Ming Tang refuge.

Tensile structures.

In 1948 a young artist, Kenned Snelson, build a sculpture made with cables of inoxidable steel that works at traction and steel pipe that works at compression. This method can be applied to the cane of bamboo of different diameter and longitudes in order to have construction with a big resistance at traction and compression.

The big longitude of the bars of bamboo make it not strong to compression.The solution to this problem is to use the bars as the steel cables and not like poles,in a way that all the loads are transmitted through tensions.

The three mountains.For the construction of a roof of 30x60 meters for a factory in Bali it was thought to use entire bars of bamboo to cover the big light of the roof.The problem was that the truss that had to support the roof had to be really high in order to make flow correctly the rain waters.The solution came,inspired by three vulcanos, that are near the site of construction.It consist in the build of three circular towers known as”skylight”.The towers consist in an interior layer of big entire bamboo bars that are turning themselves in left direction and an external layer of same size bare that are turning right. This towers can support tens of tons.

This big towers are kept together by a ring in the upper part,fixed on a side of the large bars of bamboo while on the other side a circular beam is fixed.

All the joints are made of metallic bolts cut on surface in manner that cannot be viewed.Skylights are covered by tempered glass, supported by a steel ring joined to the upper ring of laminated bamboo.

The Three towers are also support for all the windows of the building generating a perfect natural ventilation for the 300 workers of the factory.

Shell shaped structures.

The shell shape is given by the modification in size and the distribution along his longitude direction of an original simple arch shape.

In the same period in which the project of “three mountains” was developed in an another near site construction, architect Stamm was rebuilding an hall used for exposition of jewels.The precedent hall was made also with bamboo but after a big wind felt down. What happened? It was build by local carpenters that didn't consider enough the problems brought by insects that started to eat the poles. This was the cause of the collapse.

After the good behavior of the crossed poles of the skylights, Jorge Stamm elaborate a new design for the destroyed hall.

The hall elevates over an oval plant of 10x25 meters and supported by Gothic arcs. The pols of the arcs ends with a small and narrow skylight that runs all along the top roof, leaving inside small quantity of lights.

The primary structure serves as support for the secondary structure that fit together with the first structure creating a plot of rhombus.

The rhombus plot.

This plot is very rigid against stress provoked by winds and seismic actions.Shell shape construction are easy to set up and can have big dimensions for the reason that we can prolongate all the canes in an 'invisible' way and at same time guarantee a good repartition of stress.

The rhombus plot as the advantage in the no need of scaffolding as the plot can be used as stairs. This same design can be applied for smaller but transportable structures. The details of construction are simple.

For foundations its sufficient to use a big local limestone,through perforations and holes, where steel bars are introduced,becoming the joints with bamboo canes.

For the roof 's covering bamboo's fibers are tie together in bunches of 40-50cm of longitudes.

The final result is an elegant and sophisticated space, making us leaving behind the idea that bamboo is the”wood of the poor”

Curved structures.Some bamboo canes,if rolled together, can be easily curved and used for building curved surface of big scale.In smaller construction we cannot see this technique. In China even bamboo of big diameter are bended through heat in order to get the desired curvature.

Another possibility came from Japan, where Shoei Yoh bring successfully the art of wickerwork at an architectural scale. His technique consist in rolling together only the most narrow bamboo canes. Kept together only by ropes, it can be curved in any direction without big stress, maintaining the appearance of a rolled bamboo.

Examples showing the use of narrow canes rolled together.

Green school. Bali.

Both visionary and practical, the Green School is a pioneering effort to turn young

leaders away from the waste and pollution of the dominant culture, towards truly

sustainable ways of living. The School’s magnificent bamboo architecture is an outstanding example of the ecological,

spiritual and aesthetic benefits of working with nature rather than against her.

Bamboo was the material which environmentalists and designers John and Cynthia Hardy wanted to showcase it in their gorgeous Green School in Indonesia. The remarkable campus of buildings is constructed completely from sustainably-harvested bamboo and is powered by renewable energy systems. Located in Bali,has recently been shortlisted for the Aga Khan Awards for Architecture for its sustainable merits.

The project harnessed the talents of PT Bamboo, an architecture firm specializing in bamboo architecture. PT Bamboo is responsible for the bamboo portion of the Green School’s campus, which consists of four classrooms, a drop-off center, faculty housing, offices, cafes, bathrooms, a gym, and the Heart of the School, a spiraling, multi-story building for school functions.

Along with the beautiful bamboo construction, the eco-school’s curriculum focuses on sustainability and offers many scholarships to local Balinese children. The campus also includes an organic garden and utilizes a number of renewable energy systems, including a bamboo sawdust hot water and cooking system, a hydro-powered vortex generator, and solar panels. Local sustainably-grown bamboo was used exclusively throughout the campus.

Details of the different solutions for skylights.

“Empowering global citizens and green innovators who are inspired to take responsibility for the sustainability of the world”The Green School was established side-by-side with the non-profit Meranggi Foundation, which develops bamboo plantations by presenting seedlings to local rice farmers. Its an interesting point because it try to make the school and his surroundings more self sustainable as it can. For this reason the local villages are enclosed in the project with the purpose of producing food following Bio-Intensive mini-farming techniques that make it possible to grow food using:67% to 88% less water50% to 100% less fertilizer99% less energy than commercial agriculture, while using a fraction of the resources.These techniques can also produce 2 to 6 times more food..

Doors,interior walls and even all furniture is made by bamboo. Most of it,that's used for furniture, came from the waste material of the building process. The designer could express all their creativity giving birth to very interesting pieces.

Combined Structures.

Colombian Simon Velez became famous after the erection of his bamboo pavilion for the Expo2000 held in Hanover,Germany. The pavilion is not the only impressive work that he realized. The experience of the Zeri pavilion is important because obtained the license of construction without restriction by one of the most strict authorities in construction field.

Pavilion Zeni. Hanover.

Construction details1,2,3,4,5,6.

To observe the work of the structure the pavilion was built already in Manizales,Colombia.The results were so optimistic that his construction was authorized also in Germany.Only the structure of the roof and floor by bamboo. The rest is built with local species of woods.

Simon Velez.

“Every thing built in steel,I can make it in bamboo, faster and cheaper.”

Simon Velez.

Country house.Brasil.

Temple without religion. Cartagena,Colombia.

Temporal Cathedral,Pereira,Colombia.

Temporal museum Nomada

Mexico City,Mexico.

In January 2008 Mexico city show to the world the biggest bamboo structure ever made: Museum Nomada, a temporary structure composed by one nave and two aisles that was covering 5.130 mq, occupying almost the half of the biggest square of South America,Zocalo Square.

Parque de la Cultura Cafetera. Montenegro,Colombia.

Villegas, like Velez developed new models of huge bamboo roof. Usually they are supported by a concrete or wood structure.

Marcelo Villegas.

Casa Guadalupe.Santagueda,Colombia.

Chikuho city, Fukuoka,Japan.

Shoei Yoh is able to make nature the first protagonist in his architecture. The construction shown in the pictures is a tensile structure made by twisted and rolled bamboo upon which a layer or concrete is applied.This construction was built by the habitants of the community with their own bamboo.

Shoei Yoh.

Casa del Pueblo, Colombia.

The winner project of XIX Colombian biennial of Architecture. This construction of two floors ,based on a big plane,was designed and build by Simon Hosie. The architect lived for two years in the community taking part in every part of the building process.

The library is the space where we can see a particular and sophisticate mix, the traditional local material,guadua,worked with techniques of contemporary architecture.This equilibrium,between tradition brought by locals and engineering methods brought by the architect is an example of what architecture can represent in the future.

Simon Hosie.

Bamboo Pavilion Berlin,Germany.

In the Chinese tough bamboo is associated with noble qualities of

humans: resistant, honest and Humble.

Rocco Sen KeeYim.

This material,cheap an functional was chosen by Rocco Yim for the temporal space that should represent the interchange of cultures during the Vision Festival “Hong Kong and Berlin”, held in the city of Berlin. The pavilion erected in front of the house of the world's culture represent two different cultural traditions but same oriented to sustainability.

Rocco Yim is an architect born in Hong Kong.

Sands study architecture in the University of Florida, collaborator in INBAR, international network of bamboo and rattan, and helped the development of ISO, organization for bamboo structures. In 1995 founded Bamboo Living a building firm that aims to sell prefab bamboo houses in the whole world.These houses are characterized by fast construction, low cost, ecological building process and aesthetic qualities.

There are basic houses of 40 mq sold for 40.000$ to luxury houses of 240 mq sold for 400.000$

David Sands.

“The increase of bamboo as a building material is an essential step in the right direction.”

Anna Herinerg.

“For me, sustainability is a synonym for beauty: a building that is harmonious in its design, structure, technique and use of materials, as well as with the location, the environment, the user, the socio-cultural context. This, for me, is what defines its sustainable and aesthetic value.” A.H.

Vo Trong Nghia."All of my structures may look complex but they are, in fact, quite simple. Everything is modulated and it takes little time to install. A house of moderate size in a rural or suburban area will cost only about one third of the price of a normal house of the same size."

V.T.N

Kengo Kuma.

Sahabat bambu is a small but efficient company that has is base in Jogjakarta,Indonesia.I had the opportunity to visit it. A young architect heads to 'about a dozen specialized workers. What makes the difference between this company and others, is the interesting approach of Sahabat bambu towards their customers. “Sahabat” in Indonesian language means friend. Much of their time is in fact reserved for the teaching of their construction methods in small villages that are lacking of basic infrastructure. The purpose is to teach them to be self-sufficient and not depend on a government too often absent. The good results reached by the company, has brought them new funding from NGOs that organize workshops in those poor community .The success of the initiative has brought the company out of national borders,in fact ,workshops and works are already be made in Philippines, Thailand, Laos and Vietnam.

The Sahabat bambu experience.

Bamboo workshop in Nias.

Details of the joint ground-pole.

Velez

Karalynn Asem workshop.

Velez

A part of his friendly and social architecture Sahabat bambu is often collaborating in projects directed by the Indonesian architects who best know how to handle bamboo. of Indonesia

Eko Prawoto,Morisco & Sahabat bambu.

Study of construction in Pulau Gili T.

Plants. Distribution of principle poles and beams.

Details of foundations.

Details of floor structure and supporting system.

Velez

Details of joints connections.

Details of roof ' s truss.

Mechanical proprieties of bamboo.

Inner structure of bamboo.

Various kinds of vessels in a wood-fiber of Bamboo:

a. cells of parenchyma. b. annular cells.c. spiral vessels.

Testing bamboo.

Compressive strength.

Tensile strength.

Bending strength.

Elastic modules.

The fracture behavior.

Comparison of different load limit testing.

The results,as shown in the upper table, vary so much that we have to consider if there are comparable or not.

Although if we want to give approximate recommended values, we should take the lower results to stay on a safe level. Even then the bamboo still guarantees a perfect utilization of that building material.

DESIGN & bamboo.

DESIGN with bamboo.

The sword used in kendo.

Yumi,the ancient art of Japanese archery. .

Light structure for kites.

DESIGN with bamboo.

New concepts...

DESIGN with bamboo.

..and still traditional instruments.

DESIGN with bamboo.

Scaffolds.

DESIGN with bamboo.

Furniture and design.

DESIGN with bamboo.

Public and interior design.

DESIGN with bamboo.

Baskets and handcrafts.

DESIGN with bamboo.

Bamboo laminated. floors.

furniture.structure.

Literature.

Web literature.

Bamboo Preservation has been taken from “Building with bamboo: A handbook by Jules J.A. Janssen”,1995.

“Bamboo as a building material”.Dunkelberg Klaus,1992.

“Bamboo research at the Eindhoven university of technology”.Janssen, Eindhoven 1990.

“Fundamentals of the design of bamboo Structures”.Villalobos, Oscar Antonio.

Contributions from the seminar: design wit bamboo,RWTH Aachen SS 2001.

http://www.bambouseraie.com

http://humanitarianbamboo.org

http://www.bambooman.com.au

http://www.chalet-bamboo.com]

http://www.guaduabamboo.com

http://inhabitat.com

http://www.sustainablebuild.co.uk