Concrete

__**Definitions (concepts found in the text)** __  Tilt-up and tiltwall are two terms used to describe the same process. For a tilt-up concrete building, the walls are created by pouring large slabs of concrete called panels, directly at the job site, there’s no need for transportation. The size of the panels is limited only by the needs of the building and the strength of the concrete panels themselves. But because they're poured outdoors, contractors are at the mercy of climatic conditions. The precast concrete building process is similar to tilt-up construction, but without the challenges of 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. 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.
 * **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.
 * **Pozzolana** is a type of concrete used in ancient Rome made with volcanic-ash cement
 * **Reinforced concrete** is a type of concrete developed to add the tensile strength with bars of steel to the compressive strength of mass concrete.
 * __What is the difference between tiltwall construction, tilt-up panel construction and pre-cast concrete construction? (see the link for “precast concrete”)__ **


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Reinforced concrete Pre-cast concrete Prestressed concrete Concrete-shell  __**