Concrete

__Concrete __

Concrete is a manufactured mixture of cement and water, with agregates of sand and stones, which hardens rapidly by chemical combination to a stonelike, water-and fire-resisting solid of great compressive but low tensible strength.

__Reinforced concrete__: It was developed to add the tensile strength of steel to the compressive strength of mass concrete. 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 constructio__n: 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.

Reinforced concrete:

Concrete-shell construction:

Precast concrete:

Prestressed concrete:

__<span style="font-family: 'Comic Sans MS',cursive; font-size: 15px;">What is the difference between tiltwall construction, tilt-up panel construction and pre-cast concrete construction? __ <span style="font-family: 'Comic Sans MS',cursive; font-size: 15px;">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. The concrete tiltwall forms are assembled and poured directly at the job site so 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. <span style="font-family: 'Comic Sans MS',cursive; font-size: 15px;">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. <span style="font-family: 'Comic Sans MS',cursive; font-size: 15px;">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. 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. <span style="font-family: 'Comic Sans MS',cursive; font-size: 15px;">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.