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Pouring A Concrete Floor In An Existing Building

Most concrete floors are poured before construction starts so it usually possible to pour all the concrete for the slab directly from the mixer truck into the formwork. When pouring into an existing building the truck maybe able to reverse into the building – many barns have huge openings in the front to allow tractor access – if this is the case then you should ensure that you have poured your floor before you reduce the size of this opening. Check the height of the opening before ordering your readymix and ensure that the company providing the mix is aware of the height restriction.

If you don’t have a space large enough to accommodate a mixer truck then you will either have to barrow the concrete in or use a pump or conveyor system.  You need to consider how close the mixer truck can get to the building before choosing your method of delivery.  An truck with 8 cubic metres of concrete, pump and extra water on-board can weight in excess of 24tons.

Concrete – Pump or Conveyor

Concrete conveyors are only suitable for ground floors and basements, the conveyor will be wider than the pipe of a put system and so if access is difficult it may be better to use a concrete pump.  Conveyor are much cheaper than pumps.

Concrete Suppliers In France

I bought my readymix from E.Leclerc who were acting as agents for RBS (Rambaud Béton Services).  It was cheaper to buy through E.Leclerc than to go direct to RBS.  When I originally asked for a devi Point.p were a couple of hundred Euros cheaper than E.Leclerc so its worth shopping around for the best deal.  Lots of suppliers are listed on www.pagesjaunes.fr in the Béton prêt à l’emploi category.

Béton prêt à l’emploi – Concrete Suppliers

Cemex Bétons
Holcim Bétons (France-Region Ile de France)
Lafarge Bétons
Béton de Paris
Unibéton
Béton de France
Point.P Beton
Leroy Merlin Beton

France Concrete Trade Associations

FIB – Fédération de l’industrie du béton – Fabricants de matériaux de construction<

Concrete Compressive Strength

Compressive concrete strength is measured by crushing cubes of concrete l5cm per side. The concrete cubes are cured for 28 days under standardised temperature and humidity conditions before being crushed in a powerful hydraulic press. Characteristic strength values at 28 days are those below which not more than 5% of the test results fail.

The grades used for specifying the strength of concrete are C7, C10, Cl5, C20, C25, C30, C40, C50 and C60, each corresponding to a characteristic crushing strength of 7 N/mm2, 10 N/mm2 , 15 N/mm2, 20 N/mm, 25 N/mm2 etc.

Grade	Nominal mix	Use
C7 C10	1:3:81:4:6 1:3:6 1:4:5 1 :3:5	Strip footings, trench fill foundations, floors with very light traffic.
Cl5 C20	1:3:51:3:4 1:2:4 1:3:3	Foundation walls, basement walls, structural concrete, walls, reinforced floor slabs, driveways, pavings and walks,stairways.
C25 C30 C35	1:2:41:2:3 1:1.5:3 1:1:2	Domestic and commercial floors; floors subject to severe wear and tear, floors subject to harsh weather conditions,concrete roads and pavings,small bridges, concrete retaining walls and dams; poured suspended floors,
C40 C50 C60 C70 C80 C90 C100 C120		Concrete in very severe exposure; prefabricated structural elements;pre-stressed concrete used in major civil engineering projects.