For a good concrete mix, aggregates need to be clean, hard, strong particles free of Fine aggregates generally consist of natural sand or crushed stone with most if the watercement ratio is chosen correctly, a wide range in grading can be
Cement is the gray powder which forms the bonding agent when sand and course rock is mixed with water, the result is concrete. This mixture will set up into a
Apr 3, 2012 Modern concrete is cement mixed with sand and gravel at a 13/14 ratio, . Adding gravel or crushed brick will speed up the setting time.