# The composition and the proportion of concrete for the foundation

After completing all the necessary work prior to pouring the foundation, the builders often arises the problem of determining the amount of sand, gravel and cement for making concrete.The surplus would have to be poured, and with shortage - to spend time (and so is not always enough) to purchase, importation and batch of additional materials. understood that it would be desirable to avoid this and to make the flow of the concrete foundation to be optimal.In addition, a great impact on the future strength of the building or structure having the ratio of components in the premix.Proportions of concrete for the foundation are different.How do they differ, some are better suited for cottage construction - this will be discussed in this article.

** proportions of concrete for the foundation **

The composition of the mixture to fill the foundation are: cement (bind the ingredients), water (solvent), sand and gravel (as aggregate).Cement concrete fills the voids between the grains of sand and pebbles and link

type concrete | type of cement | How will the concrete mix of 10 liters cement | bulk composition of sand and gravel (P / w) per 10 liters of cement | mass composition kg |

M100 | M-400 | 78 | 41/61 | 1ts-4.6p-7.0sch |

M-500 | 90 | 53/71 | 1c-5.8p-8.1sch | |

M150 | M400 | 64 | 32/50 | 1c-3.5p-5.7sch |

M-500 | 73 | 40/58 | 1c-4.5p-6.6sch | |

M200 | M-400 | 54 | 25/42 | 1c-2.8p-4.8sch |

M-500 | 62 | 32/49 | 1c-3.5p-5.6sch | |

M250 | M-400 | 43 | 19 /43 | 1c-2.1p-3.9sch |

M-500 | 50 | 24/39 | 1c-2.6p-4.5sch | |

M300 | M-400 | 41 | 17/32 | 1c-1.9p-3.7sch |

M-500 | 47 | 22/ 37 | 1c-2.4p-4.3sch | |

M400 | M-400 | 31 | 11/24 | 1c-1.2p-2.7sch |

M-500 | 36 | 14/28 | 1c-1.6p-3.2sch | |

M450 | M-400 | 29 | 10/22 | 1c-1.1p-2.5sch |

M-500 | 32 | 12/25 | 1c-1.4p-2.9u |

Concrete M100 is used only at the initial stage of construction for reinforcement and all kinds of preparatory work, as well as in the arrangement of roads.For the basement floor building most commonly used brand M200, and in urban high-rise buildings - the M300 and M350.Kneaded concrete in an iron vessel, mixer, wooden boxes or in a special deck of iron, wood, and other available tools.Initially, the dry ingredients are mixed according to a selected proportion, and after obtaining a homogeneous mass, water is added.The result should be a thick viscous mass, which is poured into a pre-prepared formwork.If the total settlement volume of the mixture becomes quite large, filling the basement is done several times.At the same time, experts recommend to keep within one day - so get the most solid foundation.

** Calculation of **

«How much concrete foundations?" - The question is also very important.Typically, the construction of a country house its base arranged on a belt principle with wood formwork.To calculate the required height of the belt width and its total length.Consider a simple example.Let's say we have a rectangular shape the foundation of 10 x 3.6 m, height 0.21 m casting and belt width - 0.19 m. Initially considered perimeter: 2 * 3.6 * 2 + 10 = 27.2 m.Then, it is multiplied by the width and height of the casting.The result is 1.0853 m3.We hope that now with the selection and calculation of the proportion of the required amount of concrete no difficulty will arise.