Concrete

Concrete is a manufactured mixture of cement and water, with aggregates of sand and stones, which hardens rapidly by chemical combination to a stonelike, water-and-fire-resisting solid of great compressive but low tensile strength.
 * There are different types of concrete**


 * __Reinforced concrete__** was developed to add the tensile strength of steel to the compressive strength of mass concrete. It was invented (1849) by Joseph Monier, who received a patent in 1867. He exhibited his invention at the Paris Exposition of 1867.
 * __Concrete-shell construction__** permits the erection of vast vaults and domes with a concrete and steel content so reduced that the thickness is comparatively less than that of an eggshell.
 * __Precast-concrete construction__**, employs bricks, slabs, and supports made under optimal factory conditions to increase waterproofing and solidity, to decrease time and cost in erection, and to reduce expansion and contractions.
 * __prestressed concrete__** provides bearing members into which reinforcement is set under tension to produce a live force to resist a particular load. Since the member acts like a **spring**, it can carry a greater load than an unstressed member of the same size.

Principal differences between tilt wall construction, tilt-up panel construction and pre-cast concrete construction

The tilt wall construction and the tilt-up panel construction are relative similar, because both of them are worked in job site, this is particularly difficult by the weather but is less expensive than pre-cast construction. This one is worked in a fabric because the parts are made before being putted in the construction, the pre-cast method is more used when the parts of the buildings are relative small, because the transporting of large parts, make the process very expensive.