Concrete


 * CONCRETE**

** Concrete ** is a composite construction material composed primarily of aggegate, cement and water. There are many formulations that have varied properties. The aggregate is generally a coarse gravel or crushed rocks such as limestone, or granite, along with a fine aggregate such as sand. Concrete has relatively high compressive strenght, but much lower tensile strength. For this reason is usually reinforced with materials that are strong in tension (often steel). Concrete can be damaged by many processes, such as the freezing of trapped water.

Concrete is widely used for making architectural structures, pavements, footings for gates among others.



= Definitions =  Poured concrete containing steel bars or metal netting to increase its tensile strength, also called ferroconcrete. It was invented by French gardener Joseph Monier in 1849 and patented in 1867. Prior to the invention of reinforcement, concrete was strong in compression, but weak in tension. Adding reinforcement crucially increases the strength in tension. The failure strain of concrete in tension is so low that the reinforcement has to hold the cracked sections together.
 * Reinforced Concrete


 * Concrete-shell Construction

A concrete shell, also commonly called **thin shell concrete structure** , is a structure composed of a relatively thin shell of concrete, usually with no interior columns or exterior buttresses. The shells are most commonly flat plates and domes, but may also take the form of ellipsoids or cylindrical sections, or some combination thereof.




 * Precast Concrete

Precast concrete is a construction product produced by casting concrete in a reusable mold which is then cured in a controlled environment, transported to the construction site and lifted into place. In contrast, standart is poured into site-specific forms and cured on site. 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

Is a method for overcoming concrete's natural weakness in tension. It can be used to produce beams, floors or bridges with a longer span than is practical with ordinary reinforced concrete. Provides bearing members into which reinforcement is set under tension to produce a live force to resist a particular load.

**//What is the difference between tiltwall construction, tilt-up panel construction and pre-cast concrete construction?//**

**//"Several terms - tilt-up panel construction, tiltwall construction, precast concrete building construction - are used to reference new or nontraditional cement building processes. Do they all mean the same thing? If not, what are the differences?//** **//As previously stated in this article, tilt-up and tiltwall are two terms used to describe the same process. For a tilt-up concrete building, the walls are created by assembling forms and pouring large slabs of concrete called panels directly at the job site. The panels are then tilted up into position around the building's slab. Because the concrete tiltwall forms are assembled and poured directly at the job site, no transportation of panels is required. One major benefit of this is that the size of the panels is limited only by the needs of the building and the strength of the concrete panels themselves.//**

**//Tiltwall panels can sometimes be extremely wide and/or tall. Tilt-up panel have been measured at just over 69 feet across and almost 93 feet from top to bottom. Thus, architects and tilt-up concrete contractors have a great deal of flexibility in planning and creating their buildings.//** **//Because concrete tilt-up walls are poured outdoors, contractors are at the mercy of climatic conditions. When temperatures drop below freezing, curing the concrete panels becomes more difficult and expensive. This is why tilt-up construction is particularly popular in southern parts of the United States, where cold weather occurs less frequently. Certainly, tilt-up concrete buildings are built in northern areas, but the window of time for temperate weather is much smaller and less predictable, which can make construction schedules more difficult to meet.//** **//The precast concrete building process is similar to tilt-up construction, but it addresses the challenges presented by weather. For precast concrete buildings, work crews do not set up forms at the job site to create the panels. Instead, workers pre cast concrete panels at a large manufacturing facility. Because the precast concrete forms are poured indoors, this activity can take place regardless the weather conditions. After curing, the precast concrete panels are trucked to the job site. From this point, precast concrete buildings are assembled in much the same manner as tiltwall buildings.//**

**//The fact that precast concrete walls are formed at a manufacturing facility resolves the weather issue, but presents a different limitation not found in tilt-up construction. Because the panels must be transported - sometimes over long distances - places a substantial limitation on how wide or tall each panel can be. It would be impossible to load precast panels that were 60 feet wide or 90 feet long onto trucks and transport them any distance. For a precast construction project, the panels must be smaller and more manageable to allow trucks to haul them over the road to their final destination. This places greater design restrictions on architects and limits the applications where precast construction can be used.//**

**//Clearly, tilt-up or tiltwall construction and precast concrete are similar processes. Because tilt-up affords more flexibility, it is the method of choice in locations where the weather allows it. Precast concrete is a suitable choice in circumstances where environmental factors and the construction schedule preclude tiltwall as a viable option."//** [|Bob Moore Construction, Inc]

 In my opinion, the concrete is a great construction material with a lot of uses and ways to use. One important things is depending on the way you use this materials you obtain diferent textures, expressions, decorative walls, structural results, among others, and all this you got it based in only one material, its amazing! The concrete has more advantages than disadvantages and is cheaper than others constructions materials.