Some Facts About Building Materials

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Some Facts About Building Materials

hydraulic binder- гідравлічна в'яжуча речовина

crushed stone - щебінь

screenings - висівки, відсів

compressive strength — міцність на стискання

Humanity has accumulated a lot of building materials which have evolved thanks to the eternal need for construction.

The main building materials are timber, stone brick, concrete, steel, light metals, glass and plastics. Timber was one of the first materials to be used by man for constructional purposes. It is highly probable that it will be one of the last. Timber is unique among the materials of construction. It will be available when the earth's capital deposits of iron, coal, clay and the rest have been consumed. The buildings made of stone or brick are durable and fireproof, they have a poor heat conductivity. Concrete made with natural hydraulic binders was used in antiquity, particularly by the Romans. After the decline of the Roman Empire the art of making concrete has been forgotten, and the revival came much later. Concrete may be considered an artificial conglomerate of crushed stone, gravel or similar inert material with a mortar. A mixture of sand, screenings or similar inert particles with cement and water which has the capacity of hardening into a rocklike mass is called mortar.The fundamental object in proportioning concrete or mortar mixes is the production of a durable material of requisite strength, watertightness and other essential properties at minimum cost. To attain this end careful attention must be given to the selection of cement, aggregate and water. Reinforced concrete is hardly 100 years old. Today it is used in all civilized countries as one of the most important building materials. One of the essential properties of concrete is its compressive strength. Portland cement was produced more than a century ago. From the time of its first production there was a steady and gradual improvement in its compressive strength.