Not quite right. C35 is the crushing strength of concrete in
SI units. It's is a measurement of 35Mpa, which means mega
pascals. 35 therefore means a crushing strength of 35
million pascals per square metre in the mgs system, or 35
million pascals per square metre. A pascal is the SI unit of
pressure and is equal to 1 newton pressure per square metre,
ie, 35 million newtons per square metre. As a metre is a
large area, to reduce to say a mm square, we divide by
1000x1000, which is a million. This gives us 35 newtons per
quare millimetre. To give an idea in imperial measurements,
7Mpa, or C7 concrete is roughly 1,000 psi, or just under
half an imperial ton per square inch, ie, 1000/2240.
C35 is therefore roughly 5,000 psi, or 2 tons per square inch.
C35 is a fairly strong mix and would be used for say a
semi-suspended over site. For form work or strong structural
work, up to C70 can be used.
It will be C32/40, C10/15 .....(New Europan standarts,
concrete class, from 2003 year)
Here first 32 or 10 strength of concrete according with
cylinder test result, 40 or 15 are strength of concrete
according the cube result (N/mm2)
For example C32/40 concrete class old C40 grade. Old C40
also N/mm2 cube (150x150x150)mm test result
All cube result with 150x150x150 mm size of cubes. It is