fcu vs fc'

[Enhineyero]

I dont know if anyone has tried this but I was wondering if you use the design mix to form a cylinder (according to ACI) and use the same design mix to form a cube (according to BS / Eurocode)will it come up with the same strength? or atleast an insignificant difference?

I read from some other forum that it will not yield similar results and that the cube will be stronger. I dont know if that is real or the guy was just playing with us. because by theory they should be the same right?

 

[frv]

No. If I remember correctly, the European test cube is a bit smaller, and thus, the confining effect will, in fact, yield higher results.

I wouldn't worry about it though, as I am sure the Eurocode is calibrated to these test results.

 

[SMiK21]

In the Eurocode, concrete's compressive strength is specified as CXX/XX (e.g. C30/37), in MPa.

The first number is for compressive testing done in a 150 mm diameter and 300 mm high cilinder, the secondo one is for a 150 mm cube.

 

[ferrarialberto]

For concrete with strength up to 50 MPa the cylindrical strength (fck) is about 17% lower than cubic strength (fck,cube). Example, concrete grade C30/37: fck = 30 MPa, fck,cube = 37 MPa, fck = 0.83 fck,cube (approximately).

ing. FERRARI Alberto -

http://www.ferrarialberto.it

 

[slickdeals]

Agree with the above statements. A commonly used relationship that compares cylinder and cube strength is f'c = 0.8 fcu.