Name: concrete spread measured by flow table
Uploaded: 2024-11-07T14:48:28.000Z
Duration: 1 min 12 s
Channel: JoVE

The flow table test, used to find the workability of concrete and evaluate highly flowable concrete, involves an apparatus consisting of a wooden board topped with a steel plate, with a total weight of 35 pounds.
A hinge connects the board to a base, with each side of the board measuring 27.6 inches.
The upper board is designed to be lifted to a height of 1.6 inches, and the table has specific markings that guide where the concrete should be placed.
A truncated cone 8 inches high, with an 8-inch base diameter and a 5-inch top diameter, is filled with concrete. It is gently compacted, excess concrete is cleared away, and the cone mold is carefully removed after 30 seconds.
The table is jolted 15 times, with each jolt given at an interval of 4 seconds, causing the concrete to spread.
The average of the extent of spread parallel to the two edges of the table, measured after jolting, indicates the concrete&#39;s workability, with specific values corresponding to medium or high workability.

flow table test

The flow table test is an established method used to assess the workability of concrete, particularly useful for evaluating highly flowable concrete mixes. This test employs an apparatus that consists of a wooden board topped with a steel plate, collectively weighing 35 pounds. The board is connected to a base via a hinge and measures 27.6 inches on each side.
Concrete is placed within a truncated cone mold that is 8 inches high with an 8-inch base diameter and a 5-inch top diameter. The concrete is gently compacted, the excess is cleared away, and the mold is removed after 30 seconds.
The test procedure involves jolting the table 15 times at 4-second intervals by lifting the upper board to a height of 1.6 inches. This action causes the concrete to spread out from the initial cone shape. After the jolting, the extent of the spread of the concrete is measured parallel to the two edges of the table. The average spread is calculated to assess the concrete&#39;s workability. Specific values of spread are used to categorize the concrete&#39;s workability as either medium or high. This test provides crucial data on the concrete&#39;s ability to flow and settle under its own weight, reflecting its suitability for various construction applications where high fluidity and even distribution are necessary.

Flow Table Test

The flow table test, used to find the workability of concrete and evaluate highly flowable concrete, involves an apparatus consisting of a wooden board ...

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Civil Engineering

Unit 1

Fresh Concrete

KEY TERMS AND CONCEPTS

concrete spread measured by flow table

The flow table test measures how far fresh concrete spreads, which helps assess workability. Workability means how easily concrete can flow and settle under its own weight. The method is useful for highly flowable concrete mixes.

The test uses a flow table made from a wooden board with a steel plate on top. Together, the parts weigh 35 pounds. The board is hinged to a base and measures 27.6 inches on each side. A truncated cone mold is also used. It is 8 inches high, with an 8-inch base diameter and a 5-inch top diameter.

The concrete is placed in the mold and gently compacted. Then the excess is cleared away. After 30 seconds, the mold is removed. The table is jolted 15 times at 4-second intervals by lifting the upper board to a height of 1.6 inches. This motion makes the concrete spread out from its cone shape.

After jolting, the spread is measured parallel to the two edges of the table. The average spread is then calculated. This value is used to judge the concrete's workability. The results can place the mix in medium or high workability categories. The test gives useful data for construction applications that need high fluidity and even distribution.

Concrete Spread Measured by Flow Table

workability of concrete

Concrete Flow and Compaction Factors

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Concrete Workability and Mix Design Factors

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How Concrete Mixes Separate During Placement

Fresh concrete can separate during placement, which changes how the mix is spread and can weaken the finished structure. This separation is called segregation. It happens when the parts of the mix no longer stay evenly blended. Segregation often occurs when concrete moves too much inside a form. It can also happen when the mix is dropped from a great height or pushed through narrow paths with sharp turns. In these cases, the heavier coarse aggregate settles at the bottom, while lighter...

bleeding in fresh concrete

Bleeding Water and Laitance in Fresh Concrete

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Concrete Workability Check with Slump

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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...

vebe test

Concrete Workability with the Vebe Test

The Vebe test measures the workability of concrete, especially for dry mixes. Workability means how easy concrete is to handle and compact. The test uses a cylindrical chamber, a standard slump cone, and a transparent disc-shaped rider mounted on a vibrating table. The cylindrical chamber measures nine and a half inches in diameter and eight inches in height. Concrete is placed into the slump cone in layers and compacted in the standard way. After the cone is removed, the concrete stays in the...

The flow table test measures how far fresh concrete spreads, which helps assess workability. Workability means how easily concrete can flow and settle under its own weight. The method is useful for highly flowable concrete mixes. The test uses a flow table made from a wooden board with a steel plate on top. Together, the parts weigh 35 pounds. The board is hinged to a base and measures 27.6 inches on each side. A truncated cone mold is also used. It is 8 inches high, with an 8-inch base...

key terms and concepts

Measure concrete workability with the flow table test. Learn the mold size, jolting steps, and how spread is used to classify flowable mixes.

Concrete Spread Measured by Flow Table | JoVE K12

JoVE Core Civil Engineering offers a foundational exploration of essential construction materials such as bricks, stones, steel, wood, and concrete, along with fluid mechanics topics like flow over immersed bodies, open channel flow, and dimensional modeling. It also covers key surveying concepts, including leveling, traverse adjustments, curve design, topographic mapping, and geospatial technologies (GPS & GIS). Science-in-action videos showcase laboratory research on materials, fluids, and surveying practices in real-world engineering systems.

civil engineering

Concrete Spread Measured by Flow Table

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