Textiles as Structural Element for the Reinforcement of Concrete
By: Dr. Hafsa Jamshaid
Our modern-day technologies require materials bearing unusual combination of properties which cannot be present in conventional materials such as metal, ceramics and polymeric materials. It is especially evident with materials in use for construction applications. Composite materials are emerging as realistic alternatives to the metal alloys in many applications like construction, automobiles, marine, aerospace applications, sports goods, etc.
The Brief About Building Materials
By: Tabasum Rahmani
Materials used for construction purpose such as Wood, cement, aggregates, metals, bricks, concrete, clay are the most common type of building material used in construction. Many natural substances, such as clay, sand, wood and rocks, even twigs and leaves have been used to construct buildings.
Types of Building Materials Used in Construction:
Natural Construction Materials:
Construction materials can be generally categorized into two sources, natural and synthetic. Natural materials are those that are unprocessed or minimally processed by industry, such as lumber or glass. Synthetic materials are made in industrial settings after much human manipulations, such as plastics and petroleum based paints. The Mud, stone, and fibrous plants are the most basic materials, aside from tents made of flexible materials such as cloth or skins. In general stone and/or brush are used as basic structural components in these buildings, while mud is used to fill in the space between, acting as a type of concrete and insulation.
Fabric: The tent used to be the home of choice among nomadic groups the world over. Two well-known types 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 buildings can be made of flexible material such as fabric membranes, and supported by a system of steel cables or internal (air pressure.)
Mud and clay: 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 mean using the cob/adobe style, while low clay soil is usually associated with sod building. The other main ingredients include more or less sand/gravel and straw/grasses. Soil and especially clay is good thermal mass; it is very good at keeping temperatures at a constant level. Homes built with earth end to be naturally cool in the summer heat and warm in cold weather. Clay holds heat or cold, releasing it over a period of time like stone.
Rock: Rock structures have existed for as long as history can recall. It is the longest lasting building material available, and is usually readily available. Rock is a very dense material so it gives a lot of protection too, its main draw-back as a material is its weight and awkwardness. Its energy density is also considered a big draw-back, as stone is hard to keep warm without using large amounts of heating resources
Thatch: Thatch is one of the oldest of 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 favour as industrialization and improved transport increased the availability of other materials.
Brush: Brush structures are built entirely from plant parts and are generally found in tropical and subtropical areas, such as rainforests, where very large leaves can be used in the building. Native Americans often built brush structures for resting and living in, too.
Wood: 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 boards, planks and similar materials. It is a generic building material and is used in building just about any type of structure in most climates.Wood can be very flexible under loads, keeping strength while bending, and is incredibly strong when compressed vertically. Historically, wood for building large structures was used in its unprocessed form as logs. The trees were just cut to the needed length, sometimes stripped of bark, and then notched or lashed into place.
Brick and Block: A brick is a block made of kiln-fired material, usually clay or shale, but also may be of lower quality mud, etc. Clay bricks are formed in a molding (the soft mud method), or in commercial manufacture more frequently by extruding clay through a die and then wire-cutting them to the proper size (the stiff mud process). Bricks were widely used as a construction material in the 1700, 1800 and 1900s. This was probably due to the fact that it was much more flame retardant than wood in the ever crowding cities, and fairly cheap to produce. Another type of block replaced clay bricks in the late 20th century. It was the Cinder block. An important low-cost material in developing countries is the Sand Crete block, which is weaker but cheaper than fired clay bricks.
Concrete: Concrete is a composite building material made from the combination of aggregate (composite) and a binder such as cement. The most common form of concrete is Portland cement concrete, which consists of mineral aggregate (generally gravel and sand) cement and water.
Metal: 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 whose major component is iron, and is the usual choice for metal structural construction. It is strong, flexible, and if refined well and/or treated lasts a long time. Corrosion is metal’s prime enemy when it comes to longevity. The lower density and better corrosion resistance of aluminium alloys and tin sometimes overcome their greater cost. Brass was more common in the past, but is usually restricted to specific uses or specialty items today. 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 tensile strength or hardness.
Glass: 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 time keeping inclement weather outside. Glass is generally made from mixtures of sand and silicates, and is very brittle. Modern glass “curtain walls” can be used to cover the entire facade of a building. Glass can also be used to span over a wide roof structure.
Ceramics: Ceramics are such things as tiles, fixtures, etc. Ceramics are mostly used as fixtures or coverings in buildings. Ceramic floors, walls, counter-tops, even ceilings. Many countries use ceramic roofing tiles to cover many buildings. Ceramics used to be just a specialized form of clay-pottery firing in kilns, but it has evolved into more technical areas.
Plastic: Plastic pipes penetrating a concrete floor high-rise apartment building. 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.
Cement composites: Cement bonded composites are an important class of construction material. These products are made of hydrated cement paste that binds wood or alike particles or fibers to make precast 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 phenolic. These compounds are known to retard cement setting. Therefore, before using a wood in making cement boned composites, its compatibility with cement is assessed.
Virtual Building Materials: Certain materials like photographs, images, text may be considered virtual. While, they usually exist on a substrate of natural material themselves, they acquire a different quality of salience to natural materials through the process of representation.
Building Products: When we talk about Building Products, we refer to the ready-made particles that are fitted in different architectural hardware and decorative hardware parts of a building.
The list of building products exclusively exclude the materials, which are used to construct the building architecture and supporting fixtures like windows, doors, cabinets, etc. Building products do not make any part of a building rather they support and make them working.
Tabassum Rahmani, HBFCL