Precast concrete - Revision history

Designing Buildings: Reverted edits by Vmrreports (talk) to last revision by Editor

2024-08-13T20:10:01Z

Reverted edits by Vmrreports (talk) to last revision by Editor

← Older revision		Revision as of 20:10, 13 August 2024
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	* Tilt up construction.		* Tilt up construction.
	* Whittington Estate.		* Whittington Estate.
−	* [https://www.valuemarketresearch.com/report/precast-concrete-market Precast Concrete Market Report]

	[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:Construction_management]] [[Category:Construction_techniques]] [[Category:Design]] [[Category:Products_/_components]]		[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:Construction_management]] [[Category:Construction_techniques]] [[Category:Design]] [[Category:Products_/_components]]

Vmrreports at 17:07, 13 August 2024

2024-08-13T17:07:15Z

← Older revision		Revision as of 17:07, 13 August 2024
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	* Tilt up construction.		* Tilt up construction.
	* Whittington Estate.		* Whittington Estate.
		+	* [https://www.valuemarketresearch.com/report/precast-concrete-market Precast Concrete Market Report]

	[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:Construction_management]] [[Category:Construction_techniques]] [[Category:Design]] [[Category:Products_/_components]]		[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:Construction_management]] [[Category:Construction_techniques]] [[Category:Design]] [[Category:Products_/_components]]

Editor at 17:09, 21 September 2021

2021-09-21T17:09:46Z

← Older revision		Revision as of 17:09, 21 September 2021
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	* Ground beam.		* Ground beam.
	* Grouting in civil engineering.		* Grouting in civil engineering.
		+	* Precast.
	* Precast concrete cladding.		* Precast concrete cladding.
	* Prestressed concrete.		* Prestressed concrete.

Editor at 16:45, 22 June 2021

2021-06-22T16:45:17Z

← Older revision		Revision as of 16:45, 22 June 2021
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	* Cast-in-place concrete.		* Cast-in-place concrete.
	* Cellular concrete.		* Cellular concrete.
		+	* Cement-free precast product.
	* Concrete.		* Concrete.
	* Concrete frame.		* Concrete frame.

51.198.71.228: Undo revision 184002 by [[Special:Contributions/[IP address hidden]|[IP address hidden]]] ([[User talk:[IP address hidden]|talk]])

2020-11-27T15:27:26Z

Undo revision 184002 by [[Special:Contributions/[IP address hidden]|[IP address hidden]]] ([[User talk:[IP address hidden]|talk]])

← Older revision		Revision as of 15:27, 27 November 2020
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−	= Introduction ~~(1)~~ =	+	= Introduction =

	Precast concrete is a form of concrete that is prepared, cast and cured off-site, usually in a controlled factory environment, using reusable moulds. Precast concrete elements can be joined to other elements to form a complete structure. It is typically used for structural components such as; wall panels, beams, columns, floors, staircases, pipes, tunnels, and so on.		Precast concrete is a form of concrete that is prepared, cast and cured off-site, usually in a controlled factory environment, using reusable moulds. Precast concrete elements can be joined to other elements to form a complete structure. It is typically used for structural components such as; wall panels, beams, columns, floors, staircases, pipes, tunnels, and so on.

78.149.241.241 at 15:01, 27 November 2020

2020-11-27T15:01:43Z

← Older revision		Revision as of 15:01, 27 November 2020
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−	= Introduction =	+	= Introduction (1) =

	Precast concrete is a form of concrete that is prepared, cast and cured off-site, usually in a controlled factory environment, using reusable moulds. Precast concrete elements can be joined to other elements to form a complete structure. It is typically used for structural components such as; wall panels, beams, columns, floors, staircases, pipes, tunnels, and so on.		Precast concrete is a form of concrete that is prepared, cast and cured off-site, usually in a controlled factory environment, using reusable moulds. Precast concrete elements can be joined to other elements to form a complete structure. It is typically used for structural components such as; wall panels, beams, columns, floors, staircases, pipes, tunnels, and so on.

Designing Buildings at 07:41, 10 September 2020

2020-09-10T07:41:49Z

← Older revision		Revision as of 07:41, 10 September 2020
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	* Whittington Estate.		* Whittington Estate.

−	[[Category:~~Construction_management~~]] [[Category:~~Construction_techniques~~]] [[Category:~~Design~~]] [[Category:~~Products_/_components~~]] [[Category:~~DCN_Product_Knowledge~~]]	+	[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:Construction_management]] [[Category:Construction_techniques]] [[Category:Design]] [[Category:Products_/_components]]

Editor at 15:42, 24 April 2020

2020-04-24T15:42:29Z

← Older revision		Revision as of 15:42, 24 April 2020
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	* The use of concrete structures to protect construction sites.		* The use of concrete structures to protect construction sites.
	* Tilt up construction.		* Tilt up construction.
		+	* Whittington Estate.

−	[[Category:Construction_management]] [[Category:Construction_techniques]] [[Category:Design]] [[Category:Products_/_components]]	+	[[Category:Construction_management]] [[Category:Construction_techniques]] [[Category:Design]] [[Category:Products_/_components]] [[Category:DCN_Product_Knowledge]]

Designing Buildings at 12:02, 5 February 2020

2020-02-05T12:02:49Z

← Older revision		Revision as of 12:02, 5 February 2020
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	* The use of concrete structures to protect construction sites.		* The use of concrete structures to protect construction sites.
	* Tilt up construction.		* Tilt up construction.
−
−	~~= =~~

	[[Category:Construction_management]] [[Category:Construction_techniques]] [[Category:Design]] [[Category:Products_/_components]]		[[Category:Construction_management]] [[Category:Construction_techniques]] [[Category:Design]] [[Category:Products_/_components]]

86.158.61.101 at 12:01, 5 February 2020

2020-02-05T12:01:45Z

← Older revision		Revision as of 12:01, 5 February 2020
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	Structural steel frames can provide an alternative for pre-fabricated structural components, but precast concrete can be more economical and sometimes more practical. Many buildings now include a mixture of both construction techniques, sometimes incorporating structural steelwork, in-situ concrete and precast concrete elements.		Structural steel frames can provide an alternative for pre-fabricated structural components, but precast concrete can be more economical and sometimes more practical. Many buildings now include a mixture of both construction techniques, sometimes incorporating structural steelwork, in-situ concrete and precast concrete elements.

−	~~Advantages of using precast concrete include:~~	+	= Applications =

−	* It is ~~manufactured~~ in ~~a controlled environment where greater accuracy~~ and ~~better quality control~~ are ~~possible~~.	+	Reinforced concrete is usually used for structural systems due to its strength, durability, and affordability. Precast concrete is used in the following ways:
−	* ~~Reusable factory moulds mean~~ it is ~~economical~~ to produce ~~repetitive units~~.	+
−	* ~~There~~ is ~~generally less waste~~.	+	* To make beams, columns, floor slabs, foundations, and other structural members for buildings.
−	* On-~~site assembly~~ can be ~~very fast and is generally weather independent~~, ~~reducing site delays~~ and ~~ensuring~~ the construction ~~programme~~ can be ~~maintained~~.	+	* To make wall or cladding panels for buildings.
−	* Precast concrete is ~~very durable~~.	+	* To make precast pre-stressed elements for buildings.
−	* ~~There~~ are ~~fewer local environmental impacts such as dust~~ and ~~noise pollution~~.	+	* To make components for infrastructure projects: elements such as bridge spans, or metro line viaducts are often precast in a casting yard.
		+	* To make products such as precast water tanks, septic tanks, drainage chambers, railway sleepers, floor beams, boundary walls and water pipes.
		+	* As it can be moulded into any shape, it can also be used to create one-off unusual forms such as boats, sculptures and so on.
		+
		+	= Advantages of precast construction =
		+
		+	Precasting is good at producing large numbers of identical components. For example, building an affordable housing project with identical apartments could use precasting to produce wall slabs and floor slabs for all the apartments, and then lift them into place and connect them.
		+
		+	As it is done in a purpose-built precasting yard or factory, it makes construction easier for the following reasons:
		+
		+	* The construction is done on the ground rather than at height.
		+	* It can be done inside a climate-controlled structure, eliminating problems of rain, dust, cold, or heat.
		+	* Specialised formwork (moulds) can be built for doing many repetitions of the same component.
		+	* Specialised equipment can be used to make, move, and pour the liquid concrete.
		+	* Curing takes place in a controlled environment.
		+
		+	This means that the quality of precast components can be very high.
		+
		+	Since the components can be made beforehand, construction can be very quick. In cast-in-situ construction, engineers have to build each set of components after the previous set has finished, which does take time, as concrete generally takes 28 days to reach its full strength.
		+
		+	= Disadvantages of precast construction =
		+
		+	There are a few main disadvantages of precast concrete construction:
		+
		+	* Since each piece is made separately, the structural frame or system is not monolithic or continuous like regular concrete construction. The joints between pieces create structural discontinuity. The forces of the building will pass through these joints, so they have to be designed to transfer these forces safely and properly. Note that precast concrete can be used for non-structural members too.
		+	* As the building is made of discrete components, the joints between adjacent members have to be sealed with special sealants to make them waterproof
		+	* Each precast component is usually large and heavy. This means that cranes are required to lift them in position; these cranes are required to operate over the entire building volume. Since there will only be a few cranes at site, the time taken by the cranes to pick up a piece and shift it to its final position becomes critical in determining the building schedule.

	= Manufacturing process =		= Manufacturing process =
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	* Visual inspection of concrete finishes for defects.		* Visual inspection of concrete finishes for defects.
	* Locations and conditions of lifting inserts for hoisting.		* Locations and conditions of lifting inserts for hoisting.
		+
		+	= Site vs factory precasting =
		+
		+	Precasting can be carried out at a casting yard, in or near the site, or in a factory. A key aspect of determining whether to use site or factory precasting is transport costs. Factory work offers superior quality for obvious reasons, so if there is a factory close to the site, it makes sense to use it.
		+
		+	If a precasting yard is to be created, space must be laid out for the following activities:
		+
		+	* Storing the raw materials, such as cement, aggregate, sand, admixtures, water, reinforcement bars, and steel or plywood sheets for formwork.
		+	* A formwork making and maintenance yard.
		+	* A concrete mixing plant.
		+	* A steel reinforcement yard to make rebar cages to be placed inside the concrete.
		+	* A casting area.
		+	* A curing area.
		+	* A stacking area for finished components.
		+
		+	For infrastructure projects, a casting yard is created on a piece of open land in the city. It is important that this is located near a major highway, as the precast elements can be very large or heavy, and cannot be taken through narrow roads.
		+
		+	= Connecting precast concrete elements =
		+
		+	Precast concrete components can be connected in a number of ways:
		+
		+	* They can be bolted together. In order to do this, steel connectors are embedded in the concrete at the time of casting. This must be done with great precision.
		+	* They can be grouted or concreted together. In this method, loops of steel reinforcement are left protruding out of the precast concrete members. Two members are placed in position, and reinforcement is threaded between the loops. Fresh concrete is then poured around this reinforcement, in a space left for this purpose.

	= Related articles on Designing Buildings Wiki =		= Related articles on Designing Buildings Wiki =
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