Concrete


 * CONCRETE **

[[image:concrete 1.jpg width="240" height="353" align="right"]]
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.
 * Concrete ** is a manufactured



** Reinforced concrete ** was developed  to add the tensile strength of steel to the   compressive strength of mass concrete. The combination is much more versatile  than either product; it serves not only   for constructing rigid frames but also for   foundations, columns, walls, floors, and a   limitless variety of coverings, and it does   not require the addition of other structural   materials.

**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.

** The steel reinforcement **  is employed to take full   advantage of the plastic, or   sculptural, character of concrete. It can be joined or bent to  unify supporting members with   the floors and the coverings they   carry.

**What is the difference between tiltwall construction, ** **tilt-up panel construction and pre-cast ** **concrete construction? **  Tiltwall construction or called tiltwall is a new form of construction. Tiltwall construction is the new method of choice to build buildings for industries and stores. This method consists on the creation of walls by assembling. For this, walls are created horizontally pouring large slabs of concrete called panels. These panels are adjusted to the size of the structure and when builders end panels they put these walls around the building. A disadvantage of tiltwall is that panels are constructed in the place of the construction and the weather conditions limit this work. Tilt up (also called tiltwall) is considered an efficient construction method because it is a cost-effective building technique. These types of buildings are very common in North America, Australia and New Zealand. The principal material used in Tilt up is concrete. Builders constructed walls, columns, structural supports made of concrete slab. The procedure is to construct each piece horizontally, after that, it is expected that the concrete is cured. After this, the elements will tilted from horizontal to vertical with a crane and they put around the building. Tilt-up differs from prefabricationin that all elements are constructed on the job site. This eliminates the size limitation imposed by transporting elements. Precast concrete is a construction product produced by casting concrete in a reusable mold. One difference between tilt up (standard concrete) and Precast concrete is that the last is transported to the construction site. Precast Concrete is typically produced in a precast plant. Financially, the forms used in a precast plant may be reused hundreds to thousands of times before they have to be replaced, which allow cost of formwork per unit to be lower than for site-cast production. There are many different types of precast concrete. Structural applications of precast concrete include foundations, beams, floors, walls, and other structural components. It is essential that each structural component be designed and tested to withstand both the tensile and compressive loads. Tiltwall Tilt up

Precast

** CONCLUSION ** Concrete is construction material composed for cement, water with aggregates of sand and stones, gravel, limestone, granite and chemical admixtures. This material is widely used in constructs; one of its advantages is that concrete is cheap comparing with others materials. Also, with concrete can used different kind of molds to obtain the desired product forms and with the new techniques, like Tilt up the size of pieces are not problems for transport. Concrete is very strong in compression, but weak in tension. However, the reinforced concrete with steel combines the strength in compression of concrete, and the strength in tension of steel.