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The characteristics of common structural materials

• Natural materials

o Stone

o Brick/Ceramics

o Wood

o Concrete

o Metal

o Glass

• Synthetic materials

o Plastics

o Composites

o Membranes

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All structural materials have their unique characteristics. All materials must be processed and shaped to an architects or engineers specification for use in any structure. The correct materials must be selected for specific purposes. If they are used as a load bearing wall or support they must have the strength to withstand the load. If they are for decorative use load bearing is of minor concern.

Natural materials

Stone: is mineral matter; rock, and is acquired in a quarry and processed into different shapes and sizes to a builder’s specification. It has a wide range of colors, types, and hardness. Examples of common stone are quartz, marble, granite, limestone, travertine, sandstone, serpentine, and slate. Stone has great compressive strength.



Brick/Ceramics are processed clay/sand mixtures that are fired (hardened with extreme heat). Bricks/ceramics come in many assorted colors, shapes, and hardness. Ceramics are defined as inorganic, non-metallic materials. The advantage of brick as a structural material is that it is a low-density material.



Wood is a renewable building material that is easy to work. Wood comes in two basic types: hardwood and soft wood. Softwoods like pine are used primarily in framing residential structures. Hardwoods are mainly used as decorative floors and wall panels. However a small amount of hardwood is used as beams in larger buildings like churches.



Concrete is a composite material. It is made up of filler and a binder. The binder which is a cement paste (glues) the filler together to form a conglomerate. The binder is cement and water, while the filler can be fine or coarse aggregate. A fiber may be added to strengthen the mixture. The importance of the discovery of modern Portland Cement - concrete mixtures cannot be overstated, without this discovery the modern world, as we know it, could not exist. There could be no skyscrapers, road bridges, tunnels, airports, or residential foundations. Concrete is the most common structural material. It permeates every aspect of our lives.

Metals are metallically bonded compounds made from elements on the periodic table. Metals are opaque, lustrous elements. They are good conductors of heat and electricity. Many metals are malleable and ductile and are, mostly, denser than the other substances. Some examples of metals are steel, iron, copper, brass, aluminum, and tin. A common use of steel is in re-enforcing bars in concrete. Most transportation-associated bridges are made of re-enforced concrete. Check out the new Croatan Sound Bridge at the North Carolina Outer Banks. It is made of re-enforced concrete.



Glass is a mixture of ingredients, but mostly sand (silica). It is a super cooled liquid. Soda ash, potash, zinc, and bone ash can be added to lower the melting temperature. This eases the task of manufacturing glass. Glass can be clear, or it can have other elements mixed with the silica to give it a color. Examples are iron will make glass green, cobalt will make it blue, Cadmium and Selenium will make ruby red, and gold will make it cranberry.

Synthetic Materials

Plastics: Any of various organic compounds produced by polymerization. Plastic is a common name for Polymers: materials made of long strings of carbon and other elements. Each unit in a string is called a monomer and is a chemical usually derived from oil.

Composites: A complex material in which two or more distinct, structurally complementary substances, especially metals, ceramics, glasses, and polymers, combine to produce structural or functional properties not present in any individual component. A fiberglass boat hull is a composite of fiberglass cloth layers and resin. Check out the fiberglass boats made in North Carolina.

Membranes: A thin sheet of natural or synthetic material stretched on a framework. Membrane structures may or may not be rigid. A tent is an example of a membrane structure.

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History of brick

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