The flow table test or flow test is a method to determine the consistence of fresh concrete

Concrete

Concrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...

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Application
When fresh concrete is delivered to a site by a truck mixer it is sometimes necessary to check its consistence before pouring it into formwork

Formwork

Formwork is the term given to either temporary or permanent molds into which concrete or similar materials are poured. In the context of concrete construction, the falsework supports the shuttering moulds.-Formwork and concrete form types:...

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If the consistence is not correct, the concrete will not have the desired qualities once it has set, particularly the desired strength. If the concrete is too pasty, it may result in cavities within the concrete which leads to corrosion

Corrosion

Corrosion is the disintegration of an engineered material into its constituent atoms due to chemical reactions with its surroundings. In the most common use of the word, this means electrochemical oxidation of metals in reaction with an oxidant such as oxygen...

 of the rebar

Rebar

A rebar , also known as reinforcing steel, reinforcement steel, rerod, or a deformed bar, is a common steel bar, and is commonly used as a tensioning device in reinforced concrete and reinforced masonry structures holding the concrete in compression...

, eventually leading to the formation of cracks (as the rebar expands as it corrodes) which will accelerate the whole process, rather like insufficient concrete cover

Concrete cover

Concrete cover, in reinforced concrete, is the least distance between the surface of embedded reinforcement and the outer surface of the concrete...

. Cavities will also lower the stress the concrete is able to support.

Equipment

• Flow table with a grip and a hinge, 70 cm x 70 cm.
• Abrams cone, open at the top and at the bottom - 30 cm high, 17 cm top diameter, 25 cm base diameter.
• Water bucket and broom for wetting the flow table.
• Tamping rod, 60 cm height

Conducting the test

• The flowtable is wetted.
• The cone is placed on the flowtable and filled with fresh concrete in two layers, each layer 25 times tamp with tamping rod.
• The cone is lifted, allowing the concrete to flow.
• The flowtable is then lifted up several centimeters and then dropped, causing the concrete flow a little bit further.
• After this the diameter of the concrete is measured.

See also

• Concrete slump test
  Concrete slump test
  The concrete slump test is used for the measurement of a property of fresh concrete.The test is an emprical test that measures the workability of fresh concrete. More specifically, it measures the consistency of the concrete in that specific batch. It is also used to determine consistency between...
  
  
• Duff Abrams
  Duff Abrams
  Duff A. Abrams was an American researcher in the field of composition and properties of concrete. He developed the basic methods for testing concrete characteristics still in use today. A professor with the Lewis Institute, he studied the component materials of concrete in the early 20th...
  
  
• Self-consolidating concrete
  Self-consolidating concrete
  Self-consolidating concrete is characterized by a low yield, high deformability, and moderate viscosity necessary to ensure uniform suspension of solid particles during transportation, placement , and thereafter until the concrete sets.Such concrete can be used for casting heavily reinforced...
  
  

cone should be placed in centre of table.

Links and Sources

• DIN EN 12350-5
• b-i-m (German)
• Heidelberg Cement (German)
• Concrete Flow Table in an online shop