high strength concrete mix design calculator

A slump of 20–120mm is suitable for general-purpose concrete (N20 or N25). The test is repeated several times, with the average value referred to as the slump. The amount of wet concrete that ‘slumps’ away from its initial 300mm height is recorded. It is measured by filling a hollow cone mould - which is 300 millimetres high and has a 100mm diameter at the top and 200mm at the bottom - with concrete, compacting it and then removing the cone. Slump - The slump test is used to classify the workability of the concrete, which governs how easy the mix is to work and handle. Normal class concrete (‘N’) is available in grades of N20, N25, N32, N40 and N50 (the number refers to the strength in megapascals).Īpplication of concrete Strength grade (MPa)įootpaths, driveways, light footings, residential floorsĮxternal members within one kilometre of the coast Strength - Pre-mixed concrete will carry a classification which refers to the strength of the cured concrete (see Table 1). With a few workers and a decent cement mixer, a surprisingly large amount of concrete can be mixed quickly. Mixing quality concrete on-farm can be convenient and cost-effective, provided the correct steps are followed.

When rehydrated with water, the cement powder crystallises and expands, forming calcium silicates and aluminates in a chemical reaction.Ĭombined with sand and aggregate, the mix binds together to form a strong, rock-like material. It is then ground into a very fine, dehydrated powder and packed in moisture-controlled conditions. With the correct method, excellent results can be achieved whether the concrete is delivered pre-mixed or mixed on-site.Ĭement is made from a mixture of limestone, shale and clay, which is heated to a high temperature at which point it fuses.

While the process of laying concrete can be expensive, there are several options for those wishing to carry out the work themselves and save money. The most common uses of concrete are for shed floors and footings, bunkers, post footings and stockyards. With concrete being one of the most useful building materials, there are countless applications for its use on-farm.

High strength concrete mix design calculator