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

La prueba del factor de compactación determina la trabajabilidad del concreto con tamaños de agregados de hasta un máximo de una pulgada y media.
El equipo de prueba consta de dos tolvas truncadas en forma de cono con puertas batientes en la parte inferior y un cilindro, todo apilado secuencialmente, con superficies interiores pulidas para reducir la fricción.
El hormigón se coloca en la tolva superior sin compactar, y la puerta inferior se abre, permitiendo que el hormigón fluya hacia la tolva inferior.
A continuación, se abre la puerta inferior de la tolva inferior, permitiendo que el hormigón caiga en el cilindro de abajo, y se elimina el exceso de hormigón.
Se utiliza una varilla de acero para empujar y desalojar suavemente el hormigón que se atasca en una o ambas tolvas durante la prueba.
Se determina el peso final del hormigón en el volumen establecido del cilindro y se calcula la densidad para este parcialmente compactado.
La densidad completamente compactada se determina llenando el cilindro con concreto en cuatro capas y apisonando cada capa.
Por último, el factor de compactación se calcula como la relación entre la densidad del hormigón parcialmente compactado y la densidad del hormigón totalmente compactado, lo que indica la trabajabilidad de la mezcla.

prueba del factor de compactación

El ensayo del factor de compactación es un método utilizado para evaluar la trabajabilidad del hormigón. Es especialmente adecuado para mezclas de hormigón que contengan áridos de hasta 3,81 centímetros de tamaño. En este ensayo se utilizan equipos especializados que consisten en dos tolvas troncocónicas y un cilindro, todos con superficies interiores pulidas para minimizar la fricción.

El procedimiento comienza con la colocación del hormigón en la tolva superior sin compactación. Una vez llena, se abre la compuerta inferior de esta tolva, permitiendo que el hormigón fluya hacia la tolva inferior. Una vez llena la tolva inferior, se abre su compuerta inferior para dejar caer el hormigón en el cilindro situado debajo de ella. A continuación, se retira el hormigón sobrante para nivelar la superficie.

Durante la prueba, se puede utilizar una varilla de acero para empujar suavemente y desalojar el hormigón que pueda quedar atascado en las tolvas. Se registra el peso del hormigón dentro del cilindro y se calcula su densidad cuando está parcialmente compactado. A modo de comparación, la densidad del hormigón completamente compactado se determina llenando el mismo cilindro con hormigón en cuatro capas y apisonando cada capa a fondo para asegurar la máxima compactación.

El factor de compactación se calcula como la relación entre la densidad del hormigón parcialmente compactado y la densidad del hormigón totalmente compactado. Esta relación proporciona un valor numérico que indica la trabajabilidad del hormigón, y los distintos niveles del factor de compactación reflejan distintos grados de trabajabilidad. Esta prueba es fundamental para comprender cómo se comportará el hormigón cuando se coloque en moldes o encofrados durante los proyectos de construcción.

Prueba del factor de compactación

La prueba del factor de compactación determina la trabajabilidad del concreto con tamaños de agregados de hasta un máximo de una pulgada y media.
El equipo de prueba ...

Education

Educación

JoVE Core

Civil Engineering

Ingeniería Civil

Unit 1

Unidad 1

Fresh Concrete

Hormigón fresco

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

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.

civil engineering

Concrete Workability by Compacting Factor

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