Flow table test: Difference between revisions

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{{Short description|Concrete consistency test}}

{{Orphan|date=February 2009}}

[[Image:Flow Test Equipment.JPG|thumb|300px|Equipment:; flow table, UpsideAbrams down funnelcone, waterbucketwater bucket and broom for wetting the flow table.]]

[[Image:Flow Test before.JPG|thumb|300px|The upside down funnel which iscone filled up with concrete, will beprior liftedto up..lifting.]]

[[Image:Flow Test after.JPG|thumb|300px|...The anddiameter the concrete flows. After this you have to measureof the diameterresulting withflow ais folding meter stickmeasured.]]

<BR><small>These images show a flow test with very fluid concrete for a special application which made compression impossible.</small>]]

The '''flow table test''' or '''slump-flow test''' is a method to determine consistency of fresh [[concrete]]. '''Flow table test''' is also used to identify transportable moisture limit of solid bulk cargoes.<ref>{{cite web|url=http://tmltesting.com/w/index.php?title=Flow_Table_Test|title=Flow Table Test - TML Testing Wiki|website=tmltesting.com|access-date=2015-06-11|archive-url=https://web.archive.org/web/20170501222131/http://tmltesting.com/w/index.php?title=Flow_Table_Test|archive-date=2017-05-01|url-status=dead}}</ref> It is used primarily for assessing concrete that is too fluid (workable) to be measured using the [[Concrete slump test|slump test]], because the concrete will not retain its shape when the cone is removed.

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

==Application==

When fresh concrete is delivered to a site by a truck mixer, itits isconsistency sometimes necessaryneeds to checkbe its consistencechecked before pouring it intois poured theinto [[formwork]].

If consistency is not at the desired level, concrete will not have the required strength and other qualities once it has set. If concrete is too pasty, cavities may form within it. [[Rebar]] may become corroded, and concrete will crack. Cavities also reduce the concrete strength.

If the consistence is not all right, the concrete won't have the desired quality - in particular not the desired strength.

==Equipment==

During the conduction the site engineer should be around.

* Flow table with a grip and a hinge, {{convert|70|cm|in}} square. In the American version of this test, the table is {{convert|10|in|cm}} diameter per {{Citation |title=ASTM C 230|url=http://www.astm.org/Standards/C230.htm}}.

* upsideAbrams down funnel which iscone, open at the top and at the bottom - 20cm{{convert|30|cm|in}} high, 13 {{convert|17|cm|in}} top diameter, 20cm{{convert|25|cm|in}} base diameter.

* waterWater bucket and broom forto wettingwet the flow table.

* Tamping rod, {{convert|60|cm|in}} long.

==Conducting the test==

If the concrete is too pasty this might result in cavities inside the hard concrete which leads to [[corrosion]] of the [[rebar]], which again leads cracks which will accelerate the whole process - just like few [[concrete cover]]. Cavities will also lower the stress the concrete part is able to support.

* The flow table is wetted.

* The cone is placed in the center of the flow table and filled with fresh concrete in two equal layers. Each layer is tamped 10 times with a tamping rod.

* Wait 30 seconds before lifting the cone.

* The upside down funnelcone is lifted, up andallowing the concrete flowsto flow.

* The flow table is then lifted up 40mm and then dropped 15 times, causing the concrete to flow.

* After this the diameter of flow of the concrete is measured with a yardstick. The result is called "Ausbreitmaß" in German.

==EquipmentSee also==

* [[Concrete slump test]]

* Flow table with a grip and a hinge - 70 cm x 70 cm

* [[Duff Abrams]]

* upside down funnel which is open at the top and at the bottom - 20cm high, 13 cm top diameter, 20cm base diameter

* [[Self-consolidating concrete]]

* water bucket and broom for wetting the flow table

==ConductReferences==

{{Reflist}}

* The flowtable is wettened

* The upside down funnel is filled up with fresh concrete

* The upside down funnel is lifted up and the concrete flows

* The flowtable will be lifted up several centimeters and will be dropped. These commotions will make the concrete flow a little bit further.

* After this the diameter of the concrete is measured with a yardstick. The result is called "Ausbreitmaß" in German.

==LinksExternal links and Sourcessources==

*DIN EN 12350-5

*{{Citation |title=ASTM C 1437 - 15|url=http://www.astm.org/Standards/C1437.htm}} Standard Test Method for Flow of Hydraulic Cement Mortar

*[http://www.b-i-m.de/lexikon/INHALT/ausbreitv.htm b-i-m] (German)

*[http://www.betontechnischedaten.de/Kapitel11/11_1.htm#Anchor2 Heidelberg Cement] (German)

*[https://web.archive.org/web/20060928004151/http://www.controls.it/products.php?code=43&page=Workability_&_consistency&product=61&prod_name=Flow_table Concrete Flow Table in an online shop]

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[[Category:Concrete testing techniques]]

[[de:Ausbreitversuch]]