1. PRE CAST CONSTRUCTION
Ancient Roman builders made use of concrete and soon poured the material into moulds to build their complex
Precast concrete building components and site amenities are used architecturally as fireplace mantels, cladding, trim products, accessories, and curtain walls. 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 that the member will be subjected to over its lifespan.
Multi-storey car parks are commonly constructed using precast concrete. The constructions involve putting together precast parking parts which are multi-storey structural wall panels, interior and exterior columns, structural floors, girders, wall panels, stairs and slabs. These parts can be large such as double-tee structural floor modules which are lift in place at the sites by precast concrete lifting anchor systems.
Advantages
Concrete sandwich panels are highly engineered to provide rugged, durable surfaces for walls and can be used for floors, as well. Precast concrete panels (and other items) are manufactured in factory settings. Not only is this conducive to improved quality control, it’s also possible to manufacture year round during any type of weather.
By designing buildings to have one predominant panel size, panel manufacturing becomes a repetitive process and gains efficiency. Following a two-step casting process, the resulting void between panels can be filled with insulation. 
The ability to quickly erect panels at the site is another advantage of precast. Once footings are prepared, panels can be placed quickly to form the enclosure. This requires some lead time to order the panels, but is an advantage at the site. It also means that construction can be completed within a relatively small footprint and may allow building in weather that would negatively affect other types of construction. Solid, high-quality concrete construction built with an efficient use of labor makes for cost effective structures.
Early forays into this technology were done more than 100 years ago by Thomas Edison. He saw the benefit of building homes with concrete well before it was widely understood. As technology developed, improvements in forming systems and insulation materials increased the ease and appeal of using removable forms for single-family construction. These systems are strong. Their inherent thermal mass, coupled with appropriate insulation, makes them quite energy efficient. Traditional finishes can be applied to interior and exterior faces, so the buildings look similar to frame construction, although the walls are usually thicker.
The ability to quickly erect panels at the site is another advantage of precast. Once footings are prepared, panels can be placed quickly to form the enclosure. This requires some lead time to order the panels, but is an advantage at the site. It also means that construction can be completed within a relatively small footprint and may allow building in weather that would negatively affect other types of construction. Solid, high-quality concrete construction built with an efficient use of labor makes for cost effective structures.
Precast, like all concrete construction, provides fire, rot, termite, and molds resistance. Exterior walls can withstand tornado-force winds. It is solid construction that protects occupants from weather and from natural disasters.
2.Removable Forms (Cast-In-Place)
Cast-in-place (CIP) concrete walls are made with ready-mix concrete placed into removable forms erected on site. Historically, this has been one of the most common forms of building basement walls. The same techniques used below grade can be repeated with above-grade walls to form the first floor and upper levels of homes.
Early forays into this technology were done more than 100 years ago by Thomas Edison. He saw the benefit of building homes with concrete well before it was widely understood. As technology developed, improvements in forming systems and insulation materials increased the ease and appeal of using removable forms for single-family construction. These systems are strong. Their inherent thermal mass, coupled with appropriate insulation, makes them quite energy efficient. Traditional finishes can be applied to interior and exterior faces, so the buildings look similar to frame construction, although the walls are usually thicker.
The technology for casting concrete in removable forms—the beginning of the reinforced concrete construction industry—dates back at least to the 1850s, not long after portland cement was patented. The predominant use of removable forms for single-family homes was for below-grade (basement) walls. Thomas Edison was one of the first to recognized the potential for above-grade applications and do some demonstration projects, several single-family homes made entirely of concrete.
Advantages
Cast-in-place provides benefits to builders and building owners alike.
Owners appreciate:
- strong walls
- safety and disaster resistance
- molds, rot, mildew, and insect resistance
- sound-blocking ability
- for insulated systems, energy efficiency and resultant cost savings
Contractors and builders like:
- familiarity
- expands business to include more than basements
- cost effective building technology
3.HOLLOW BLOCKS CONSTRUCTION
Concrete blocks are made from cast concrete, i.e. Portland cement and aggregate, usually sand and fine gravel for high-density blocks. Lower density blocks may use industrial wastes as an aggregate. Lightweight blocks can also be produced using aerated concrete.Those that use cinders (fly ash or bottom ash) are called cinder blocks in Canada, the US and New Zealand, breeze blocks (breeze is a synonym of ash) in the UK and New Zealand,hollow blocks in the Philippines and are also known as better blocks or bricks in Australia. Clinker blocks use clinker as aggregate. In non-technical usage, the terms cinder block and breeze block are often generalize to cover all of these varieties.
Concrete blocks may be produced with hollow centres to reduce weight or improve insulation. The use of blockwork allows structures to be built in the traditional masonry style with layers (or courses) of staggered blocks. Blocks come in many sizes. In the US, with an R-Value of 1.11 the most common nominal size is 16 × 8 × 8 in (410 × 200 × 200 mm); the actual size is usually about 3⁄8 in (9.5 mm) smaller to allow for mortar joints. In Ireland and the UK, blocks are usually 440 × 215 × 100 mm (17.3 × 8.5 × 3.9 in) excluding mortar joints. In New Zealand, blocks are usually 390 × 190 × 190 mm (15.4 × 7.5 × 7.5 in) excluding mortar joints.
Block cores are typically tapered so that the top surface of the block (as laid) has a greater surface on which to spread a mortar bed. There may be two, three or four cores, although two cores are the most common configuration. The presence of a core allows steel reinforcing to be inserted into the assembly, greatly increasing its strength. Reinforced cores are filled with grout to secure the reinforcing in proper relationship to the structure, and to bond the block and reinforcing. The reinforcing is primarily used to impart greater tensile strength to the assembly, improving its ability to resist lateral forces such as wind load and seismic forces.
A variety of specialized shapes exist to allow special construction features. U-shaped blocks or notches allow the construction of bond beams or lintel assemblies, using horizontal reinforcing grouted into place in the cavity. Blocks with a channel on the end, known as "jamb blocks", allow doors to be secured to wall assemblies. Blocks with grooved ends permit the construction of control joints, allowing a filler material to be anchored between the un-mortared block ends. Other features, such as radiused corners known as "bullnoses" may be incorporated. A wide variety of decorative profiles also exist.
Concrete masonry units may be formulated with special aggregates to produce specific colors or textures for finish use. Special textures may be produced by splitting a ribbed or solid two-block unit; such factory-produced units are called "split-rib" or "split-face" blocks.Blocks may be scored by grooves the width of a mortar joint to simulate different block modules (e.g., an 8" x 16" block may be scored in the middle to simulate 8" x 8" masonry), with the grooves filled with mortar and struck to match the true joints.
Q : Which are in these three features of Construction are the best?
A: As what I have learn base on this different Construction Cast in Place and Pre Cast is used in putting up fly over, MRT, Rail Train, houses and Buildings. While, Hollow Blocks used in construction of the house and wall of the Buildings.
Q: What countries used Pre Cast and Cast in Place?
A: So many countries used these modern Pre cast and Cast in Place like Europe, Middle East,America, Australia, and Asia.
Q: Are these two Construction process are durable ?
A: These Construction process are durable as long the contractor follow the right process and right amount of materials they will used.
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