Flow table test: Difference between revisions

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{{Short description|Concrete consistency test}}

[[Image:Flow Test Equipment.JPG|thumb|300px|Equipment; flow table, upside down funnel, waterbucket and broom.]]

[[Image:Flow Test beforeEquipment.JPG|thumb|300px|TheEquipment; upsideflow downtable, funnelAbrams filledcone, withwater concretebucket priorand to liftingbroom.]]

[[Image:Flow Test afterbefore.JPG|thumb|300px|The diametercone offilled thewith resultingconcrete, flowprior isto measuredlifting.]]

[[Image:Flow Test after.JPG|thumb|300px|The diameter of the resulting flow is measured.]]

<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 pouringit itis poured into [[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.

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]].

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]] of the [[rebar]], 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]]. Cavities will also lower the stress the concrete is able to support.

During the test the site engineer should be present.

==Equipment==

* 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 - 30cm{{convert|30|cm|in}} high, {{convert|17 |cm|in}} top diameter, 25cm{{convert|25|cm|in}} base diameter.

* Flow table with a grip and a hinge, 70 cm x 70 cm.

* Water bucket and broom forto wettingwet the flow table.

* Upside down funnel which is open at the top and at the bottom - 30cm high, 17 cm top diameter, 25cm base diameter.

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

* Water bucket and broom for wetting the flow table.

* Tamping rod.(60 cm height)

==Conducting the test==

* The flowtableflow table is wetted.

* The upside down funnelcone is placed onin the flowtablecenter of the flow table and filled with fresh concrete. in two layerequal eachlayers. Each layer 25is timestamped tamp10 times with a tamping rod.

* The flowtable is wetted.

* Wait 30 seconds before lifting the cone.

* The upside down funnel is placed on the flowtable and filled with fresh concrete.in two layer each layer 25 times tamp with tamping rod.

* The funnelcone is lifted up, allowing the concrete to flow.

* The flowtableflow table is then lifted up several centimeters40mm and then dropped 15 times, causing the concrete flowto a little bit furtherflow.

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

* flow table fill with wet concrete

==See also==

* [[Concrete slump test]]

* [[Duff Abrams]]
* [[Self-consolidating concrete]]

==References==

==Links and Sources==

{{Reflist}}

==External links and sources==

*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]]

[[it:Prova di spandimento]]