Rebar in the context of "Concrete"

Steel is an alloy of iron and carbon that demonstrates improved mechanical properties compared to the pure form of iron. Due to its high elastic modulus, yield strength, fracture strength and low raw material cost, steel is one of the most commonly manufactured materials in the world. Steel is used in structures (as concrete reinforcing rods or steel beams), in bridges, infrastructure, tools, ships, trains, cars, bicycles, machines, electrical appliances, furniture, and weapons.

Iron is always the main element in steel, but other elements are used to produce various grades of steel, demonstrating altered material, mechanical, and microstructural properties. Stainless steels, for example, typically contain 18% chromium and exhibit improved corrosion and oxidation resistance versus their carbon steel counterpart. Galvanized steel is coated in a layer of zinc to achieve a similar effect. Under atmospheric pressures, steels generally take on two crystalline forms: body-centered cubic and face-centered cubic; however, depending on the thermal history and alloying, the microstructure may contain the distorted martensite phase or the carbon-rich cementite phase, which are tetragonal and orthorhombic, respectively. In the case of alloyed iron, the strengthening is primarily due to the introduction of carbon in the primarily-iron lattice, inhibiting deformation under mechanical stress. Alloying may also induce additional phases that affect the mechanical properties. In most cases, the engineered mechanical properties are at the expense of the ductility and elongation of the pure iron state, which decrease upon the addition of carbon.

Building material is material used for construction. Many naturally occurring substances, such as clay, rocks, sand, wood, and even twigs and leaves, have been used to construct buildings and other structures, like bridges. Apart from naturally occurring materials, many man-made products are in use, some more and some less synthetic. The manufacturing of building materials is an established industry in many countries and the use of these materials is typically segmented into specific specialty trades, such as carpentry, insulation, plumbing, and roofing work. They provide the make-up of habitats and structures including homes.

Reinforced concrete, also called ferroconcrete or ferro-concrete, is a composite material in which concrete's relatively low tensile strength and ductility are compensated for by the inclusion of reinforcement having higher tensile strength or ductility. The reinforcement is usually, though not necessarily, steel reinforcing bars (known as rebar) and is usually embedded passively in the concrete before the concrete sets. However, post-tensioning is also employed as a technique to reinforce the concrete. In terms of volume used annually, it is one of the most common engineering materials. In corrosion engineering terms, when designed correctly, the alkalinity of the concrete protects the steel rebar from corrosion.

An endoskeleton (from Ancient Greek ἔνδον (éndon), meaning "inside", and σκελετός (skeletós), meaning "skeleton") is a structural frame (skeleton) — usually composed of mineralized tissue — on the inside of an animal, overlaid by soft tissues. Endoskeletons serve as structural support against gravity and mechanical loads, and provide anchoring attachment sites for skeletal muscles to transmit force and allow movements and locomotion.

Vertebrates and the closely related cephalochordates are the predominant animal clade with endoskeletons (made of mostly bone and sometimes cartilage, as well as notochordal glycoprotein and collagen fibers), although invertebrates such as sponges also have evolved a form of "rebar" endoskeletons made of diffuse meshworks of calcite/silica structural elements called spicules, and echinoderms have a dermal calcite endoskeleton known as ossicles. Some coleoid cephalopods (squids and cuttlefish) have an internalized vestigial aragonite/calcite-chitin shell known as gladius or cuttlebone, which can serve as muscle attachments but the main function is often to maintain buoyancy rather than to give structural support, and their body shape is largely maintained by hydroskeleton.

Filler materials are particles added to binders (resin, thermoplastics, cement) to make a composite material. Filler materials improve specific properties or make the product cheaper.

Coarse filler materials such as construction aggregate and rebar are used in the building industry to make plaster, mortar and concrete.

Formwork is molds into which concrete or similar materials are either precast or cast-in-place. In the context of concrete construction, the falsework supports the shuttering molds. In specialty applications formwork may be permanently incorporated into the final structure, adding insulation or helping reinforce the finished structure.