Notes tagged
concrete
3 notes on concrete. All notes.
Concrete grades: what M25 actually means
The number in M25 is a characteristic strength in newtons per square millimetre at 28 days. Not an average, not a mix ratio, and not a promise about today.
The concrete cube test, and the four weeks you wait
Cubes are cast on site, cured, crushed and recorded. Most of what goes wrong with the test happens in the first ten minutes, long before the crushing.
The slump test, and why water is the real argument
Slump measures how far fresh concrete settles when its mould is lifted. It takes two minutes, and it is the only check between you and a weaker structure.