Name: concrete workability by compacting factor
Uploaded: 2024-11-07T14:48:28.000Z
Duration: 1 min 22 s
Channel: JoVE

The compacting factor test determines the workability of concrete with aggregate sizes up to a maximum of one and a half inches.
The test equipment consists of two truncated cone-shaped hoppers with hinged doors at the bottom and a cylinder, all stacked sequentially, with polished interior surfaces to reduce friction.
Concrete is placed in the top hopper without compacting, and the bottom door is opened, letting the concrete flow into the lower hopper.
Next, the bottom door of the lower hopper is opened, allowing the concrete to fall into the cylinder below, and the excess concrete is struck off.
A steel rod is used to gently poke and dislodge the concrete that gets stuck in one or both hoppers during the test.
The final weight of the concrete in the cylinder&#39;s set volume is determined, and the density for this partially compacted is calculated.
Fully compacted density is determined by filling the cylinder with concrete in four layers and tamping each layer.
Finally, the compacting factor is calculated as the ratio of the density of partially compacted concrete to the density of fully compacted concrete, which indicates the workability of the mix.

compacteringsfactortest

De compacteringsfactortest is een methode die wordt gebruikt om de verwerkbaarheid van beton te beoordelen. Het is vooral geschikt voor betonmengsels die aggregaten bevatten tot 3,81 centimeter groot. Deze test omvat gespecialiseerde apparatuur bestaande uit twee afgeknotte kegel vormige trechters en een cilinder, allemaal met gepolijste binnen oppervlakken om wrijving te minimaliseren.

De procedure begint met het plaatsen van beton in de bovenste trechter zonder enige verdichting. Zodra deze is gevuld, wordt de onderste deur van deze trechter geopend, waardoor het beton in de onderste trechter kan stromen. Nadat de onderste trechter is gevuld, wordt de onderste deur geopend om het beton in de cilinder eronder te laten vallen. Overtollig beton wordt vervolgens weggeslagen om het oppervlak te egaliseren.

Tijdens de test kan een stalen staaf worden gebruikt om voorzichtig beton dat vast kan komen te zitten in de trechters los te maken. Het gewicht van het beton in de cilinder wordt geregistreerd en de dichtheid ervan wanneer het gedeeltelijk is verdicht, wordt berekend. Ter vergelijking wordt de volledig verdichte dichtheid van het beton bepaald door dezelfde cilinder te vullen met beton in vier lagen en elke laag grondig aan te stampen om maximale verdichting te garanderen.

De verdichtingsfactor wordt berekend als de verhouding van de dichtheid van het gedeeltelijk verdichte beton tot de dichtheid van het volledig verdichte beton. Deze verhouding biedt een numerieke waarde die de verwerkbaarheid van het beton aangeeft, waarbij verschillende niveaus van de verdichtingsfactor verschillende graden van verwerkbaarheid weerspiegelen. Deze test is cruciaal om te begrijpen hoe het beton zich zal gedragen wanneer het in mallen of vormen wordt geplaatst tijdens bouwprojecten.

Compacteringsfactortest

The compacting factor test determines the workability of concrete with aggregate sizes up to a maximum of one and a half inches.
The test equipment ...

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Compacting Factor test

concrete workability by compacting factor

The compacting factor test measures the workability of concrete. Workability describes how easily concrete can move and fill a mold or form during construction. This test is especially suitable for concrete mixes with aggregates up to one and a half inches in size.

The setup uses specialized equipment with two truncated cone-shaped hoppers and a cylinder. All of the inside surfaces are polished to reduce friction. Concrete is first placed into the upper hopper without any compaction. Then the bottom door is opened so the mix can flow into the lower hopper.

After the lower hopper fills, its bottom door is opened. The concrete falls into the cylinder below. Extra concrete is struck off to make the surface level. If concrete gets stuck in the hoppers, a steel rod may be used to gently poke it loose.

Next, the weight of the concrete in the cylinder is recorded. This gives the density of the partially compacted concrete. For comparison, the same cylinder is filled with concrete in four layers and each layer is tamped thoroughly to reach maximum compaction. The compacting factor is then calculated as the ratio of the partially compacted density to the fully compacted density. This number shows the workability of the concrete and helps predict how the mix will behave in forms.

Concrete Workability by Compacting Factor

concrete-workability-by-compacting-factor

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compacting factor test

The compacting factor test measures the workability of concrete. Workability describes how easily concrete can move and fill a mold or form during construction. This test is especially suitable for concrete mixes with aggregates up to one and a half inches in size. The setup uses specialized equipment with two truncated cone-shaped hoppers and a cylinder. All of the inside surfaces are polished to reduce friction. Concrete is first placed into the upper hopper without any compaction. Then the...

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key terms and concepts

Measure concrete workability with the compacting factor test using hoppers and a cylinder. Learn how partially and fully compacted densities are compared.

Concrete Workability by Compacting Factor | JoVE K12

JoVE Core Civil Engineering provides a foundational exploration of essential construction materials in civil engineering, focusing on bricks, stones, steel, wood, and concrete through easy-to-understand animated videos. This collection covers the properties, manufacturing processes, and practical applications of these materials. Additionally, the accompanied science-in-action videos demonstrate the research experiments performed in laboratories.

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Concrete Workability by Compacting Factor

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