buildin material

8/7/2019 Buildin Material

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Building Material Industry Profile

With the advent of modern civilization and development of scientific knowledge, there has been

an upsurge in demand for developing newer materials for novel applications. In fact, with the

technological leaps in recent times, focus has been on developing the materials required toperform in stringent conditions - high temperature & pressure, highly corrosive environment,higher strength but without much weight implications etc. which the conventional materials

failed to service. This ushered in 'engineered material', devising material properties catering tothe application needs. And the innovation was not limited to developing materials with novel

properties alone but it also addressed the method of manufacturing - improved processingtechniques, effective use of energy while processing and more importantly with the least

environmental impact. Advanced materials with combination of properties for specific end usesbecame a reality.

Over the last thirty years composite materials, plastics, and ceramics have been the dominant

emerging materials. The volume and number of applications of composite materials has grownsteadily, penetrating and conquering new markets relentlessly. Modern composite materials

constitute a significant proportion of the engineered materials market ranging from everydayproducts to sophisticated niche applications.

Today high performance fibre reinforced plastics (FRP) are starting to challenge those ubiquitous

materials such as steel & aluminium in everyday applications as diverse as automobile bodiesand civil infrastructure. It would be naive to suggest that FRP will dislodge those materials from

their dominant roles. However, continuous advances in the manufacturing technologies andperformance of FRP have intensified the competition in a growing range of applications leading

to significant growth in its market acceptance. For any given application and industry sector, thefinal choice is often a competitive outcome of alternative solutions, including advances in

alternative materials such as aluminium alloys and metal-composite hybrids. Each type ofcomposite brings its own performance characteristics that are typically suited for specific

applications.

Increasingly enabled by the introduction of newer polymer resin matrix materials and highperformance reinforcement fibres of glass, carbon and aramid, the penetration of these advanced

material forms has witnessed a steady expansion in usage. The increased consumption hasreduced the product cost. High performance FRP can now be found in such diverse applications

as composite armouring designed to resist explosive impacts, fuel cylinders for natural gasvehicles, windmill blades, industrial drive shafts, support beams of highway bridges and even

paper making rollers. An examination of the diversity of some of these newer applications andthe socio-commercial considerations that underpin their introduction gives an instructive insight

into the future place of high performance FRP.

The development of a composite component involves both material and structural design. Unlikeconventional materials, the properties of the composite material can be varied considering the

end application. Properties (stiffness, thermal expansion etc.) can be varied continuously over abroad range of values by suitable selection of resin, fibre, their ratio, additives etc.


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Commonly used polymer matrix composites comprise a thermosetting resin matrix in

combination with a fibrous reinforcement. Some advanced thermoplastic resins are also used,whilst some composites employ mineral filler reinforcements, either alone or in combination

with fibrous types. Cellular reinforcements (foams and honeycombs) are also used to impart

stiffness in conjunction with ultra lightweight. Whilst the use of composites will be a clearchoice in many instances, material selection in others will depend on factors such as workinglifetime requirements, number of items to be produced (run length), complexity of product shape,

possible savings in assembly costs and on the experience & skills of the designer in tapping theoptimum potential of composites.

Lightweight corrosion resistant materials such as FRP could provide an important contribution to

the safe, economical development of resources. The need for new markets has spurred renewedefforts in reducing the cost of both raw materials and manufacturing processes, making

composites more competitive to use in civil infrastructure applications. The mechanicalproperties of composite laminates are listed in Table-I.

Indian efforts centre around developing cost effective building materials as well as for catering to

the housing needs of urban & rural poor. In this context, certain developments concerning glassfibre reinforced polymer composites, natural fibre composites, industrial waste based composites

have assumed importance. The key restricting factors in the application of composites are initialcosts due to raw materials and also inefficient conventional moulding processes.

Various key product applications being developed in the building & construction industry are

prefabricated, portable & modular buildings, exterior cladding panels, interior decorations,furniture, bridges and architecture mouldings. Various proven composite products being used in

the housing sector are bathtubs & basins, drainage channels, manhole covers, pits, farmbuildings, doors, door frames & windows, cabinets, housing modular, sheeting roof and flat,

structural members, portable toilets, ponds & fountains, water storage tanks etc.

Composites for Structural ApplicationsComposites have long been used in the construction industry. Applications range from non-

structural gratings and claddings to full structural systems for industrial supports, buildings, longspan roof structures, tanks, bridge components and complete bridge systems. Their benefits of

corrosion resistance and light weight have proven attractive in many low stress applications.Composites present immense opportunities to play increasing role as an alternate material to

replace timber, steel, aluminium and concrete in buildings.

Road BridgesBridges account for a major sector of the construction industry and have attracted strong interest

for the utilization of high performance FRP. FRP has been found quite suitable for repair,seismic retrofitting and upgrading of concrete bridges as a way to extend the service life of

existing structures. FRP is also being considered as an economic solution for new bridgestructures. Design approaches and manufacturing efficiencies developed for road bridge

applications will benefit their introduction into a broader range of civil construction fields.


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Decks for both pedestrian and vehicle bridges across waterways, railways and roadways are nowa commercial reality in both North America and Europe, with some pedestrian bridges being

built entirely from composites. Because of the superior durability of composite, only cosmeticmaintenance requirements are expected for at least 50 years. The composite bridge decks are

quite suitable for replacing conventional/old bridge decks having super structure intact. The

replacement can be carried out in a short time with minimal disturbance to the traffic.

Pultruded ProfilesAmong a wide array of composite products, pultruded profiles such as gratings, ladders, cabletrays, solid rods & other sections are used in many structural application with Class I flame

retardancy. Pultrusion is the most cost-effective method for the production of fibre-reinforcedcomposite structural profiles. It brings high performance composites down to commercial

applications such as lightweight corrosion-free structures, electrical non-conductive systems,offshore platforms and many other innovative new products. Pultruded sections are well-

established alternative to steel, wood and aluminium in developed countries and are fast catchingup in other parts of the world. Structural sections have ready markets in oil exploration rigs,

chemical industries etc. The amount of energy required to fabricate FRP composite materials forstructural applications with respect to conventional materials such as steel & aluminium is lower

and would work for its economic advantage in the end. The pultruded products are already beingrecognized as commodity in the international market for construction.

In pursuit of developing advanced performance materials for building & construction, railways,

automobiles, bio-medical etc., the Advanced Composites Programme was launched byTechnology Information, Forecasting & Assessment Council (TIFAC), an autonomous

organization under the Department of Science & Technology (DST), Govt. of India. Under aproject of the aforesaid programme, FRP Pultruded profiles (industrial gratings, solid rods for

electrical insulation, cable-trays, ladders etc.) with excellent surface finish and flame retardancyas per international standards have been developed by M/s. Sucro Filters Pvt. Ltd., Pune. The

profiles developed have met all the desired properties. Table II lists the mechanical/ chemicalproperties of FRP pultruded sections vs. other structural materials. Table III lists out the

characteristics of the pultruded products.

Repair, Retrofit & RebarsComposite plates are successfully used to repair masonry beams, columns, buildings and other

structures damaged/weakened by impact, earthquake or subsidence and can usually be adhered inplace by hand without the need for heavy lifting equipment. Such repairs can be carried out

much more rapidly than traditional techniques.Composite reinforcing bars may be used toreplace steel in conventional reinforced concrete in order to prevent "concrete cancer" problems

resulting from internal corrosion of the reinforcement. The use of composite rebars is justifiedwhere the nature of the construction would render possible future repairs inaccessible or

otherwise unduly costly.

Composites as Building MaterialThe composite is an ideal material for the manufacture of prefabricated, portable and modular

buildings as well as for exterior cladding panels, which can simulate masonry or stone. Thetranslucent roof sheeting is now supplied in a variety of colours and profiles to suit both


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commercial and domestic building needs. In interior applications, composites are used in themanufacture of shower enclosures and trays, baths, sinks, troughs and spas. Cast composite

products are widely used for the production of vanity units, bench tops and basins. Realisticsimulation of marble in various colours, onyx and granite can now be achieved with cast

composites using resin, filler and proper processing technology. The availability of highly fire

resistant phenolic composites opens up the opportunity for new, safer and cost effective buildingtechniques.

This area holds priority for the induction of composites in place of conventional materials beingused in doors & windows, paneling, furniture and other interiors. Components made of

composite materials find extensive applications in shuttering supports, special architecturalstructures imparting aesthetic appearance, large signages etc. with the advantages like longer life,

low maintenance, ease in workability, fire retardancy etc. The key restricting factors in theapplication of composites are initial costs due to raw materials and also inefficient conventional

moulding processes. Industry & design experts are of the view that with the adoption ofadvanced technologies and some extent of standardization, these problems could be easily taken

care of.

FRP Doors & Door FramesWith the scarcity of wood for building products, the alternative, which merits attention is to

promote the manufacturing of low cost FRP building materials to meet the demands of thehousing & building sectors. The doors made of FRP skins, sandwiched with core materials such

as rigid polyurethane foam, expanded polystyrene, paper honeycomb, jute/coir felt etc. can havepotential usage in residential buildings, offices, schools, hospitals, laboratories etc. As structural

sandwich construction has attained broad acceptance & usage for primary load bearingstructures, the FRP doors can be manufactured in various sizes & designs using this technology.

The principal fabrication technique employed is contact moulding or hand lay-up process. The

front & back sheets of the doors are fabricated separately. Wooden inserts are placed betweentwo sheets for various fittings. The PU foam is sandwiched between the sheets by in-situ

foaming process followed by painting & polishing to meet aesthetic requirement. Proper usage ofadditives imparts fire retardant properties to the doors. In addition, usage of composite material

for the doors makes them totally water & termite resistant. FRP doors are much cheaper than thewooden ones. The FRP doorframes can also be fabricated by contact moulding.

The FRP doors & doorframes have been designed & developed using the aforesaid technology

by the RV-TIFAC Composite Design Centre (CDC), Bangalore under the Advanced CompositesProgramme. The FRP doors developed by CDC conform to BIS specifications (IS:4020). After

successful field trials and users feedback, the technology for FRP door has been transferred toover 50 entrepreneurs for commercial exploitation.

The rapid expansion of the use of sandwich construction in many fields has yielded a more

precise knowledge of design methods, test procedures & manufacturing techniques of cost-effective composite products. A low-density core made of honeycomb or foam materials

provides a structural performance with minimum weight. Other considerations such as soundinsulation, heat resistance, vibration-damping etc. dictate the particular choice of material used


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as core material.

Ceiling PanelThe fibre glass veil facing used while moulding the panels for suspended ceilings increases panel

stiffness and resists puncturing. Due to their easy printability, the veil imparts good panel

aesthetics. The suspended ceilings are used to cover up electrical wiring, ducting, piping andfittings. The veil with an optimum porosity contributes to improved acoustical quality of theworking or living space.

FRP Modular Toilet Units for Indian RailwaysFRP Modular Toilet Units for Railway Coaches were developed under a project of the AdvancedComposites Programme in partnership with Hindustan Fibreglass Works, Vadodara with design

and technology support from IIT-Bombay. The Industrial Design Centre of IIT-B helped indesign drawing, fabrication of modular toilets with improved aesthetics & ergonomics. IIT-B

also extended support in terms of structural design of FRP toilets, reinforcement lay-up, moulddesign & fabrication, selection of suitable raw materials, testing & mechanical characterization

and quality assurance norms for fabrication. Three types of FRP toilet units were developed asper the space availability in ICF coaches.

The FRP toilet unit consists of four parts : the flooring trough, one L-shaped side-wall, one C-

shaped side-wall & roof. These parts are fastened by self-tightening screws. The FRP toilet islight in weight, corrosion resistant, fire retardant, has longer life with easy maintainability. Due

to its modular design, the whole toilet unit can be installed inside the coach in a short timeframe.The following features were provided in the toilet .

y FRP sandwich door with rigid PUF core, lipped with pultruded FRP frame on all foursides of the door

y Special PVC sheet with improved anti-skid and anti-abrasion properties for theflooring

y Concealed type Ki-tech flexible conduits with aluminium core encased within twoHDPE layers

FRP toilet units are now fully operational in passenger coaches of Indian Railways. Theperformance of four nos. FRP toilets, which were fitted to an AC-II tier coach of Mumbai

Rajdhani Express in October 2001, has been extremely satisfactory. Based on the initial fieldtrials, FRP toilets have been inducted by the Indian Railways for many important trains on

regular basis. The project bagged the Certificate of Merit under the National Award forExcellence in Consultancy Services2001 by DSIR, Govt. of India.

Natural Fibre Composites as Building MaterialsNatural fibres, as a substitute for glass fibres in composite components, have gained interest in

the last decade, especially in the housing sector. Fibres like flax, hemp or jute are cheap, havebetter stiffness per unit weight and have a lower impact on the environment. Structural

applications are rare since existing production techniques are not applicable and availability ofsemi-finished materials with constant quality is still a problem.


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The moderate mechanical properties of natural fibres prevent them from being used in high-performance applications (e.g. where carbon reinforced composites would be utilized), but for

many reasons they can compete with glass fibres. Advantages and disadvantages determine thechoice. Low specific weight, which results in a higher specific strength and stiffness than glass is

a benefit especially in parts designed for bending stiffness.

Natural fibre composites (NFC) can be used as a substitute for timber as well as for a number ofother applications. It can be moulded into sheets, boards, gratings, pallets, frames, structural

sections and many other shapes. They can be used as a substitute for wood, metal or masonry forpartitions, false ceilings, facades, barricades, fences, railings, flooring, roofing, wall tiles etc. It

can also be used in pre-fabricated housing, cubicles, kiosks, awnings, sheds/shelters. Naturalfibres due to their adequate tensile strength and good specific modulus enjoy the right potential

for usage in composites thus ensuring a value-added application avenue. The maximum tensile,impact and flexural strengths for natural fibre composites reported so far are 104.0 MN/m2 (jute-

epoxy), 22.0 kJ/m2

(jute-polyester) and 64.0 MN/m2 (banana-polyester) respectively.

Although the tensile strength and Youngs modulus of natural fibre like jute are lower than thoseof glass fibres, the specific modulus of jute fibre is superior to that of glass and on a modulus per

cost basis, jute is far superior. The specific strength per unit cost of jute, too, approaches that ofglass. The need for using jute fibres in place of the traditional glass fibre partly or fully as

reinforcing agents in composites stems from its lower specific gravity (1.29) and higher specificmodulus (40 GPa) of jute compared with those of glass (2.5 & 30 GPa respectively). Apart from

much lower cost and renewable nature of jute, much lower energy requirement for theproduction of jute (only 2% of that for glass) makes it attractive as a reinforcing fibre in

composites. Table IV gives the properties of a few natural fibre.

y Tensile strength strongly depends on type of fibre, being a bundle or a single filamentJute-CoirCompositesJute-coir composites provide an economic alternative to wood for the construction industry. It

involves the production of coir-ply boards with oriented jute as face veneer and coir plus wasterubber wood inside. A very thin layer of jute fibres impregnated with phenolic resin is used as

the face veneer for improved aesthetics and to give a wood like finish.

The orientation & uniformity of jute fibre improve with carding and this also helps in betterpenetration of resin into the fibre. The coir fibre contains 45.84% lignin as against 39% in

teakwood. Therefore, it is more resistant than teakwood against rotting under wet and dryconditions and has better tensile strength. The composite boards namely, coir-ply boards (jute +rubber wood + coir) as plywood substitute and natural fibre reinforced boards (jute + coir) as

MDF substitute can be used in place of wood or MDF boards for partitioning, false ceiling,surface paneling, roofing, furniture, cupboards, wardrobes etc. These boards have been employed

as doors & door frames as an alternate to conventional material like wood, steel etc.

Bamboo Composite Boards & LaminatesBamboo is one of the fastest renewable plant with a maturity cycle of 3-4 years, thus making it a

highly attractive natural resource compared to forest hardwoods. Bamboo offers good potential


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for processing it into composites as a wood substitute. Bamboo laminates could replace timber inmany applications such as furniture, doors & windows and their frames, partitions, wardrobes,

cabinets, flooring etc.

Bamboo laminates are made from slivers milled out from the bamboo culm. After primary

processing comprising cross cutting, splitting and 2-side planing, the slivers are treated for starchremoval and prevention of termite/borer attack. The slivers are then subjected to hot air dryingfollowed by 4-side planing for attaining uniform thickness. These slivers are coated with glue on

the surface and are arranged systematically. They are subjected to a curing in a hot press (6X42-day light) at temp. ~ 70 0C using steam & pressure ~ 17 Kg/cm2. The pressed laminate

(panels/tiles) is then put through trimming, sanding & grooving machines to give a pre-finishshape. The flow chart & intermediate quality control parameters for manufacturing bamboo

composites are enclosed.

The project on production of bamboo composites & laminates is based on the followingpremises.

y Value-added products from Bambooy Cost-effective compared to good solid wood sections for furniturey Diversification from traditional plywood to bamboo based productsy Complete range of bamboo composite laminates for furniture, flooring tiles, boards, door

& window frames to replace the use of timber for domestic as well as international

markety Expected Benefitsy Bamboo composite based flooring tiles, boards (used for partitions, cupboards, racks,

door & window panels) and blocks (used for furniture, rails & styles for doors &

windows etc.) as wood substitute would help develop & promote high value-addedproducts from bamboo

y Bamboo composite laminates with a low-temperature curing resin system for reducedenergy requirement

y Promotion of eco-friendly use of bamboo while building a sustainable infrastructure forplant multiplication, propagation and cultivation

y Boosting the usage of bamboo based products in India towards generating goodemployment & income opportunities at rural level

Towards an effective bamboo utilization and exploring the value-addition potential, the project

on development of bamboo composite laminates was launched by the Advanced CompositesProgramme of TIFAC in partnership with M/s. Emmbee Forest Products Pvt. Ltd., Manabariwith technology support from the Department of Polymer Science & Technology, University of

Calcutta. The project aimed at developing value-added products from bamboo with an innovativeresin system for reduced processing energy requirement. Bamboo based products such as

flooring tiles, laminate boards, blocks (for door & window frames, rails & styles, furniture etc.)as wood substitute are being developed under the project.

For preventing bamboo composites from any deterioration by moisture absorption and imparting

long-term storage life, a water based acrylic pre-coat has been developed. This pre-coat would


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prevent any fungal attack during transit for the reconstituted wood sections for furniture. Further,a UV cured melamine acrylate system as the finishing coat has also been developed for flooring

tiles made of bamboo composites. A water based PU resin system has also been tried for finalfinish of the flooring tiles.

Various stages of bamboo processing starting from cross-cutting, parallel splitting, knot removal,two-side planning, anti-fungal treatment, drying, four-side planning, glue application and hotpressing were fine tuned. Products such as flooring tiles, furniture sections, reconstituted wood,

air locked sections, mat boards etc. have been developed under the project.

Composite Materials towards Re-building & RehabilitationIn the wake of disastrous damages by the earthquake in Gujarat, the Advanced Composites

Programme has contributed to the national efforts of re-building and rehabilitation. Under theTIFAC Rehab Project for Kachchh, the following initiatives were taken up for the quake affected

people.

392 low-cost semi-permanent shelters (20x12) made of natural fibre composite materialssuch as jute-coir composite boards and rice husk particle boards with bamboo mat face veneer

etc. were supported on MS angles & channels. For improved aesthetics and also to augment thethermal insulation, natural fibre composite board roofing of the shelters was covered with

terracotta tiles.

In order to cater to the shelters, 128 community toilet blocks (4x4) made of modular FRPsection for walls & roof were constructed.Fifteen shops (12x8) were constructed in the

township along with a Post Office in the township, which has commenced its services. Inaddition to the semi-permanent residential shelters constructed at Bhuj, 25 school blocks-cum-

community centres (24x 20) were also constructed at various locations in Kachchh.

The TIFAC Rehab Project was a model initiative of technology demonstration with novelbuilding materials with the delivery in the quickest possible time addressing the crucial need for

post-disaster relief.

Composite Building Materials Technology DemonstrationFor augmenting the reception block of Technology Bhavan campus in Delhi, the Advanced

Composites Programme took initiatives by building a 3000 sq. ft. temporary structure for postoffice, CR section, technology demonstration-cum -display area and additional office space

towards showcasing composite building materials. The array of products developed under theprogramme such as jute-coir boards, FRP doors, bamboo composite flooring tiles & rice husk

particle boards for false ceiling were used in the construction of the shelter towards technologydemonstration. Jute-coir composite boards, made of coir felt & waste rubber-wood as inside

veneers and oriented jute as face veneer is a unique value-added application for agro-wastes andpositioned as an effective wood substitute building material. While the shelter structure was

fabricated out of standard steel sections, jute-coir boards were used for double-wall constructionensuring excellent thermal insulation. They were also used for roofing overlaid with terracotta

tiles. Elegant looking bamboo composite tiles were used for the flooring. The door shutters madeof sandwich panels of glass fibre reinforced polyester resin, have good aesthetic appeal with


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adequate mechanical strength and water resistance.

ConclusionThe most important feature governing the choice of material & form of construction for any

component is its structural integrity. Whereas high specific strength and lightweight were often

the dominant criteria to be achieved, particularly for aerospace applications, there is today anincreasing emphasis on other criteria such as environmental durability, embedded energy, fireresistance.

Innovative thermoset and natural fibre composite products would go a long way in developing

new application areas thus enhancing its market reach. India with an excellent knowledge-base invarious resins, catalysts & curing systems coupled with an adequate availability of various raw

materials can certainly carve out a niche in the upcoming technology of composite fabrication.Value-added novel applications of natural fibre composites would also ensure international

market for cheaper substitutes. The products when locally manufactured would actually becomecost competitive for other wood substitutes.

The Advanced Composites programme has improved the laboratory-industry linkages towards

application development & commercialization by launching 30 projects across the country. Theprogramme has been quite instrumental in bridging the knowledge gaps and bringing together

the industries & the users for technology development, transfer & subsequent commercialization.

Building material is any material which is used for a construction purpose. Many naturally

occurring substances, such as clay, sand, wood and rocks, even twigs and leaves have been used

to construct buildings. Apart from naturally occurring materials, many man-made products are in

use, some more and some less synthetic. The manufacture of building materials is an establishedindustry in many countries and the use of these materials is typically segmented into specific

specialty trades, such as carpentry, plumbing, roofing and insulation work. They provide the

make-up of habitats and structures including homes.

Fabric

The tent used to be the home of choice among nomadic groups the world over. Two well knowntypes include the conical teepee and the circular yurt. It has been revived as a major construction

technique with the development of tensile architecture and synthetic fabrics. Modern buildingscan be made of flexible material such as fabric membranes, and supported by a system of steelcables, rigid framework or internal (air pressure.)

Mud and clay


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The amount of each material used leads to different styles of buildings. The deciding factor is

usually connected with the quality of the soil being used. Larger amounts of clay usually meanusing the cob/adobe style, while low clay soil is usually associated with sodbuilding. The other

main ingredients include more or less sand/gravel and straw/grasses. Rammed earth is both anold and newer take on creating walls, once made by compacting clay soils between planks by

hand, now forms and mechanical pneumatic compressors are used.

Soil and especially clay is good thermal mass; it is very good at keeping temperatures at aconstant level. Homes built with earth tend to be naturally cool in the summer heat and warm incold weather. Clay holds heat or cold, releasing it over a period of time like stone. Earthen walls

change temperature slowly, so artificially raising or lowering the temperature can use moreresources than in say a wood built house, but the heat/coolness stays longer.

Peoples building with mostly dirt and clay, such as cob, sod, and adobe, resulted in homes that

have been built for centuries in western and northern Europe as well as the rest of the world, andcontinue to be built, though on a smaller scale. Some of these buildings have remained habitable

for hundreds of years.

Rock


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Mont Saint Michel

Rock structures have existed for as long as history can recall. It is the longest lasting building

material available, and is usually readily available. There are many types of rock throughout the

world all with differing attributes that make them better or worse for particular uses. Rock is a

very dense material so it gives a lot of protection too, its main draw-back as a material is itsweight and awkwardness. Its energy density is also considered a big draw-back, as stone is hardto keep warm without using large amounts of heating resources.

Dry-stone walls have been built for as long as humans have put one stone on top of another.

Eventually different forms of mortar were used to hold the stones together, cement being themost commonplace now.

The granite-strewn uplands of Dartmoor National Park, United Kingdom, for example, providedample resources for early settlers. Circular huts were constructed from loose granite rocks

throughout the Neolithic and early Bronze Age, and the remains of an estimated 5,000 can still

be seen today. Granite continued to be used throughout the Medieval period (see Dartmoorlonghouse) and into modern times. Slate is another stone type, commonly used as roofingmaterial in the United Kingdom and other parts of the world where it is found.

Mostly stone buildings can be seen in most major cities, some civilizations built entirely with

stone such as the Pyramids in Egypt, the Aztec pyramids and the remains of the Inca civilization.

Thatch

Thatch is one of the oldest of building materials known; grass is a good insulator and easily

harvested. Many African tribes have lived in homes made completely of grasses year round. In

Europe, thatch roofs on homes were once prevalent but the material fell out of favor asindustrialization and improved transport increased the availability of other materials. Today,though, the practice is undergoing a revival. In the Netherlands, for instance, many new

buildings have thatched roofs with special ridge tiles on top.

Brush

Toda tribe hut


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Brush structures are built entirely from plant parts and are generally found in tropical and sub-tropical areas, such as rainforests, where very large leaves can be used in the building. Native

Americanes for resting and living in, too. These are built mostly with branches, twigs and leaves,and bark, similar to a beaver's lodge. These were variously named wikiups, lean-tos, and so

forth.

Ice

Ice was used by the Inuit for igloos, but has also been used for ice hotels as a tourist attraction innorthern areas that might not otherwise see many winter tourists.

Concrete

Falkirk Wheel

Concrete is a composite building material made from the combination of aggregate and a bindersuch as cement. The most common form of concrete is Portland cement concrete, which consists

of mineral aggregate (generally gravel and sand), portland cement and water. After mixing, the

cement hydrates and eventually hardens into a stone-like material. When used in the genericsense, this is the material referred to by the term concrete.

For a concrete construction of any size, as concrete has a rather low tensile strength, it isgenerally strengthened using steel rods or bars (known as rebars). This strengthened concrete is

then referred to as reinforced concrete. In order to minimize any air bubbles, that would weakenthe structure, a vibrator is used to eliminate any air that has been entrained when the liquid

concrete mix is poured around the ironwork. Concrete has been the predominant buildingmaterial in this modern age due to its longevity, formability, and ease of transport. Recent

advancements, such as Insulating concrete forms, combine the concrete forming and otherconstruction steps (installation of insulation). All materials must be taken in required proportions

as described in standards.

Metal


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MIT Stata Center

Metal is used as structural framework for larger buildings such as skyscrapers, or as an external

surface covering. There are many types of metals used for building. Steel is a metal alloy whosemajor component is iron, and is the usual choice for metal structural building materials. It is

strong, flexible, and if refined well and/or treated lasts a long time. Corrosion is metal's primeenemy when it comes to longevity.

The lower density and better corrosion resistance of aluminum alloys and tin sometimes

overcome their greater cost. Brass was more common in the past, but is usually restricted tospecific uses or specialty items today.

Metal figures quite prominently in prefabricated structures such as the Quonset hut, and can be

seen used in most cosmopolitan cities. It requires a great deal of human labor to produce metal,especially in the large amounts needed for the building industries.

Other metals used include titanium, chrome, gold, silver. Titanium can be used for structural purposes, but it is much more expensive than steel. Chrome, gold, and silver are used as

decoration, because these materials are expensive and lack structural qualities such as tensilestrength or hardness.

Glass


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British Museum Great Court

Glassmaking is considered an art form as well as an industrial process or material.

Clear windows have been used since the invention of glass to cover small openings in a building.

They provided humans with the ability to both let light into rooms while at the same timekeeping inclement weather outside. Glass is generally made from mixtures of sand and silicates,

in a very hot fire stove called a kiln and is very brittle. Very often additives are added to themixture when making to produce glass with shades of colors or various characteristics (such as

bullet proof glass, or light emittance).

The use of glass in architectural buildings has become very popular in the modern culture. Glass

"curtain walls" can be used to cover the entire facade of a building, or it can be used to span overa wide roof structure in a "space frame". These uses though require some sort of frame to hold

sections of glass together, as glass by itself is too brittle and would require an overly large kiln tobe used to span such large areas by itself.

Plastic

Plastic pipes penetrating a concrete floor in a Canadian high rise apartment building


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The term plastics covers a range of synthetic or semi-synthetic organic condensation or polymerization products that can be molded or extruded into objects or films or fibers. Their

name is derived from the fact that in their semi-liquid state they are malleable, or have the property of plasticity. Plastics vary immensely in heat tolerance, hardness, and resiliency.

Combined with this adaptability, the general uniformity of composition and lightness of plastics

ensures their use in almost all industrial applications today.

Foam

Foamed plastic sheet to be used as backing for firestop mortar at CIBC bank in Toronto.

More recently synthetic polystyrene or polyurethane foam has been used in combination withstructural materials, such as concrete. It is light weight, easily shaped and an excellent insulator.

It is usually used as part of a structural insulated panel where the foam is sandwiched betweenwood or cement or insulated concrete forms where concrete is sandwiched between two layers of

foam.

Cement composites

Cement bonded composites are made of hydrated cement paste that binds wood or alike particlesor fibers to make pre-cast building components. Various fibrous materials including paper and

fiberglass have been used as binders.

Wood and natural fibers are composed of various soluble organic compounds like carbohydrates,

glycosides and phenolics. These compounds are known to retard cement setting. Therefore, before using a wood in making cement boned composites, its compatibility with cement is

assessed.


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Wood-cement compatibility is the ratio of a parameter related to the property of a wood-cementcomposite to that of a neat cement paste. The compatibility is often expressed as a percentage

value. To determine wood-cement compatibility, methods based on different properties are used,such as, hydration characteristics, strength, interfacial bond and morphology. Various methods

are used by researchers such as the measurement of hydration characteristics of a cement-

aggregate mix, the comparison of the mechanical properties of cement-aggregate mixes and thevisual assessment of micro structural properties of the wood-cement mixes. It has been foundthat the hydration test by measuring the change in hydration temperature with time is the most

convenient method. Recently, Karade all have reviewed these methods of compatibilityassessment and suggested a method based on the maturity concept i.e. taking in consideration

both time and temperature of cement hydration reaction.

Modern industry

Modern building is a multibillion dollar industry, and the production and harvesting of rawmaterials for building purposes is on a world wide scale. Often being a primary governmental

and trade keypoint between nations. Environmental concerns are also becoming a major worldtopic concerning the availability and sustainability of certain materials, and the extraction of such

large quantities needed for the human habitat.

Building products

In the market place the term buildingproducts often refers to the ready-made particles/sections,

made from various materials, that are fitted in architectural hardware and decorative hardware parts of a building. The list of building products exclusively exclude the building materials,

which are used to construct the building architecture and supporting fixtures like windows,doors, cabinets, etc. Building products do not make any part rather they support and make them

working in a modular fashion.

buildin material

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