BUILDING MATERIALS
INTRODUCTION
Building materials is any materials which is used for construction purposes, or building materials are those items which are used for the building of houses and other structure.
There are many varieties of products utilized for building residences. In some countries building materials are used according to the weather conditions of that place.
Basically the building materials are identified into two (2) types that is the synthetic and natural products.
The synthetic building materials are those which are manufactured or man-made products and are in use, some more and some less synthetic.
The manufacture of building materials is an established industry in many countries and use of these material is typically segmented into specific specially trades, such as carpentry, insulation, plumbing and roofing work.
They provide the make-up of habitats and structures including homes. While the natural product are those which have actually been stemmed naturally. Many naturally occurring substance, such as clay, rock, sand, and wood, even twigs and leaves have been used for construction of building.
– Mud / Clay is one of the most commonly used building materials which consist of clay in addition to mud. Both products are utilized to construct homes or houses.
Clay based building usually come in two distinct types, one being when the wall are made directly with the mud mixture and the other being walls built by stacking air-dried building block called mud bricks. Other uses of clay in building is combined with straws to create light clay, wattle and daub, also mud plaster.
Clay usually means using the cob style, while low clay soil is usually associated with sod building. The other main ingredients include more or less sand or gravel and straw or gases.
–Rock: has been considered as the oldest building materials made use of for building houses. It is the greatest and most long lasting material utilized for construction. Though it was commonly made use of in old time. It is now not in used but used as facing materials.
Rock is the longest lasting building material available and is used usually readily available. Rock is very dense material so it gives a lot of protection. Its main draw back as a material is its weight and that it is hard to keep warm with using large amounts of heating resources.
Stone or rock structures have existed for as long as history can recall, there are many types of rock throughout the world all with differing attribute that make them better or worse for particular uses. Rock is a very dense material so it gives a lot of protection too, and awkwardness. Its energy density is also considered a big drawback, as stone is hard to 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 stones together, cement being the most common place now.
Stone buildings can be seen in most major cities, some civilization built entirely with stone such as the Egyptian and Artes pyramids and the structure of the Inea civilization
Sand: Sand is used with cement and sometimes, lime to make mortar for mansonry work and plaster sand is also used as a part of the concrete mix. An important low-cost building material in the countries with high sand content soils is the sandcrete block, which is whether weaker but cheaper than fired clay brick.
Wood and Timber
Wood has been used as a building material for thousands of years in its natural state. Today, engineered wood is becoming very common in industrialized countries.
Wood is a product of trees, and sometimes other fibrous plants, used for construction purposes when cut or pressed into lumber and timber such as board, planks and similar materials. It is generic building material and it is used in building just about any types of structure in most climates. Wood can be very flexible under loads, keeping strength, while bending, and is incredibly strong when compressed vertically. There are many differing qualities to the different types of wood, even among same trees species. This means specific species are better suited for various uses than others. And growing condition are important for deciding quality.
Timber is the term used for construction purposes except the term is used in the united states. Raw wood becomes timber when the wood has been converted (split, hewn, sawn) in the forms of minimally processed logs stacked on top of each other, timber frames construction, and light-frame construction. The main problem with timber structure are fire risk and moisture-related problem.
In modern times softwood is used as a lower-value bulk materials, whereas hardwood is usually used for finishings and furniture. Historically timber frame structure were built with oak in western Europe, recently Douglas firm has become the most popular wood for most types of structural building.
Wood; unlike steel, and concrete, whose chief degradation mechanisms are chemical reactions the principal degradation mechanism for wood are biological attacks, namely decay and termites.
Decay fungi, feed on wood and require oxygen, mild temperatures and moisture to thrive, most damaging fungi affect wood only when the moisture constant is above the fibre saturation point. So preventing decay is usually a matter of keeping moisture away. Several species of termite can damage wood, but most damage is due to subterranean termites. The usual method for preventing subterranean termite infestation is to prevent access, that is isolating wood from the ground surface and thereby denying the termite a bridge to the structure.
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 and sand year-round. In Europe, thatch roofs on homes were once prevalent but the material fell out of favour as industrialization and improved transport increased the availability of other materials. Today, though the practice is undergoing a revived. In the Netherlands, for instance, many new building have thatched roofs with special ridge tiles on top.
Twigs and leaves
Are also one of the oldest of building materials. Leaves is a good conductor of fire resistance and can easily harvested.
Man-made product are:
Concrete: Concrete structures are also durable and strong. It is been made of gravel, sand, cement and a little water. Concrete is made use for construction of homes and work places.
Concrete is a composite building materials made from the combination of aggregate and a binder such as cement. The most common form of concrete is Portland cement, concrete, which consists of mineral aggregate (generally gravel) and sands, Portland cement and water.
After mixing, the cement hydrates and eventually hardens into a stone-like material. When used in the generic sense, this is the material referred to by the term concrete.
For a concrete construction of any sizes, as concrete has a rather low tensile strength, it is generally strengthen 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 weaken the 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 building material in the modern age due to its longevity, formability, and ease of transport. Recent advancements such as insulating concrete forms, combine the concrete forming and other construction steps. (installation of insulators). All materials must be taken in required proportions as described in standards.
CEMENT COMPOSITES
Cement bonded composites are made of hydrated cement paste that binds wood, particles or fibers to make pre-cast building components. Various fibrous materials including paper fiber plants and carbon-fiber have been used as binders.
Wood and natural fibers are composed of various soluble organic compounds like carbonhydrates glycosides and phenolics. These compounds are known to ratered cement setting. Therefore, before using a wood in making cement bonded composites, its compatibility with cement is assessed.
Wood cement compatibility is the ratio of a parameter related to the property of a wood-cement composite to that of a neat cement paste. The compatibility is often expressed as a percentage value. The determine wood-cement compatibility method based on different properties are used, such as hydration characteristic, strength interfacial bond and morphology, various method are used by researchers such as measurement of hydration characteristic of a cement-aggregate mix. The comparison of the mechanical properties of cement-aggregate mixed, and the visual assessment of microstructural properties of the wood-cement mixes. It has been found that the hydration test by measuring the changes in hydration temperature with time is the most convenient method. Recently, Karade etal have reviewed these method of compatibility assessment and suggested a method based on the maturity concept. i.e. taking in consideration both time and temperature of cement hydration reactions.
FIRED BRICK AND CLAY BLOCKS
Bricks are made in a similar way to mud-bricks except without the fibrous binder such as strew and are fired (burned in a blick clamp or klin) after they have air dried to permanently harden them. Klin fired clay bricks are a ceramic material. Fired bricks can be solid or have hollow cavities to aid in drying and make them lighter and easier to transport. The individual bricks are placed upon each other in courses using mortar. Successive courses being used to build up wells arches, and other architectural element. Fired brick wells are usually substantially thinner than cab/adobe while keeping the same vertical strength. They require more energy to create but are easier to transport and store, are lighter than stone blocks. Romans extensively used fired brick of a shapes and types now called Roman bricks. Building with brick gained much popularity in the mid 18th century and 19th centuries. This was due to lower cost with increases in brick manufacturing and fire-safety in the over crowding cities.
The cinder block supplemented or replaced fired bricks in the late 20th century often being used for the inner parts of masonry wells and by themselves structural clay tiles (cloy blocks) are clay or terracotta and typically are perforated with holes.
METAL
Metal is used as structural framework for large building such as skyscrapers or as an external surface covering. There are many types of metal used for building. Metal figures quite prominently in prefabricated structure such as the Quonset hut, can be seen used in most cosmopolitan cities. It requires a great deal of human labour to produce metal especially in the large amounts needed for the building industries. Corrosion is metal prime enemy when it comes to longevity.
– Steel is a metal alloy whose major component is iron, and is the usual choice for metal structural building materials. It is strong flexible, and if refined well or treated lasts a long time.
– The lower density and better corrosion resistance of aluminum alloys and tin sometimes overcome their greater cost.
– Copper is a valued building materials because of its advantageous properties. These include corrosion resistance, durability low thermal movement, light weight, radio frequency shielding, lightning, protection, sustainability, recyclability and a wide ranges of finishes copper is incorporated into roofing, flashing, gutters downspouts, domes, spires, vaults, well cladding, building expansion joints and indoor design element.
– Other metals used include chrome, gold, silver, and titanium, titanium can be sued for structural purposes, but it is much more expansive than steel. Chrome gold and silver are used as decoration, because these materials are expensive and lack structural quantities such as tensile strength or hardness.
Plastics
The term plastics covers a ranges of synthetic or semi-synthetic organic condensation or polymerization products that can be molded or extroded into objects, 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 very immensely in heat tolerance, hardness, and resilience, combined with this adaptability the general uniformity of compensation and lightness of characteristics ensures their use in almost all industrial application today. High performance plastics, such as ETFE have become an ideal building material due to its high abrasion resistance and chemical inertness.
Notable building that feature it include the Bejing National Aquatic Center and the Eden project biomas.
Plastic is also commonly use for building materials such as plastic pipelines, tubes etc are also important for any home or office.
Glass
Glass making 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 opening in a building. Glass panel provided human with the ability to both let light into rooms while at the same time keeping inclement weather outside.
Glass is generally made from mixture of sand and silicates, in a very hot fire stove called a kiln and is very brittle. Additives are often included the mixture used to produces glass with shades of cokers 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 wells can be sued to cover the entire facade of a building or it can be used to span over a wide roof structure in a space frame. These uses though require some sort of frame to hold section of glass together, as glass by itself is too brittle and would require an overly large kiln to be used to span such large areas by itself.
Glass bricks were invented in the early 20th century.
GYPCRETE
Gypcrete is a mixture of gypsum plaster and fibre glass rovings. Although plaster and fibrous plaster have been used for many years, especially for ceiling, it was not until the early 1990s that serious studies of the strength and qualities of a walling system. Rapid wall, using a mixture of gypsum plaster and 300mm pluss fibre glass rovings, were investigated. It was discovered, through testing of the University of Adelaide, that these wall had significant, load bearing shear and lateral resistance together with earthquake – resistance, fire resistance and thermal properties.
With an abundance of gypsum (naturally occurring and by-product chemical FGD and phosphor gypsums) available world-wide, gypcrate – based building products, which are fully recycleable, offer significant environmental benefits.
FABRIC
The tent is the home of choice among nomadic groups all over the world. The well known types include the conical teepee and the circular yart. The tent has been revived as a major construction techniques with the development of tensile architecture and synthetic fabrics. Modern buildings can be made of flexible materials such as fabric membranes and supported by a system of steel cables, rigid or internal or by air pressure.
FOAM
Recently, synthetic polystyrene or polyarethane foam has been used in combination with structural materials, such as concrete. It is lightweight, easily shaped and excellent insulator. Foam is usually used as part of a structural insulated panel, where in the foam is sandwiched between wood or cement or insulating concrete forms.
ICE AND SNOW
Snow and occasionally ice were used by the Inuit people for igloos and snow is used to built a shelter called a quinzhere. Ice has also been used for ice hotels as a tourist attraction in northern climate. It is materials which is used by the Inuits.
BRUSH
Bruch structure are built entirely from plant parts and were used in primitive cultures such as Native Americans, pyging peoples in Africa. These are built mostly with branches twigs and leaves and bark, similar to a beaver’s ledge. There were variously named lean-tos and so forth.
An extension on the brush building ideas is the wattle and daub process in which clay soil or dung usually cow, are used to fill in and cover a woven brush structure. This gives the structure more thermal mass and strength. Wattle and daub is one of the oldest building techniques. Many older timber frame building incorporate wattle and daub as non load bearing walls between the timber frames.
PAPERS AND MEMBRANES
Building papers and membranes are used for many reason in construction. One of the oldest building papers is red rosin paper which was known to be in used before 1850 and was used as an underlayment in exterior walls, roofs and floors and for protecting a jobsite during construction. Tar paper was invented late in the 19th century and was used for similar purposes as rosin paper and far gravel roofs. Tar paper has largely fallen out of use supplanted by asphalt felt paper. Felt paper has been supplanted in some uses by systematic underlayment particularly in roofing by synthetic underlayment’s and siding by house wraps. There are a wide variety of damp proofing and waterproofing membranes used for roofing basement waterproofing and geomembranes.
CERAMICS
Fire clay bricks have been used since the time of the Roman. Special tiles are used for roofing, siding, flooring, ceiling, pipes, flue liners and more.
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